Best Linux Tools and Applications to install on a perfect Desktop or WebServer

This is a shared collection of Linux tools to run the perfect server or desktop. 

A "perfect" software configuration has to be specialized per machine taking into requirements both functional and structural parameters. We cannot be too general, as some packages depends on the hardware, some depends on the functionality expected, some are dually depending on these but this package selection for Unix/Linux - especially RedHat can be used to configure a very good multifunctional Linux machine, including :

-Office Tools
-Design and Multimedia
-Electronics and Robotics
-CAD
-Internet
-Mathematics
-Networking
-System Management
-Development
-Web Server
-...etc

A large selection of Linux softwares and packages .rpm was done. We passed in in review the advices from internet users and a strict selection was operated on each fedora spins software configuration recently released to establish a list of most interesting packages for a first configuration (V1) in august 2014.

This gives an extraordinary potential of applications in a large number of activities. Some softwares are really top ! Some are just the best of existing solutions in a particular domain and it's not easy to ensure many characteristics of the systems are not regressive with their explosion.

For a detailed package list, please see this incredible selection of all .rpm : on this link.
(download the .txt file)

This list can be used to install quickly your Red Hat / fedora and other Linux flavors using yum : 

[root@server x]# yum -y install $(cat installed.txt)

This command with install all .rpm included in this configuration.

To get the list of installed packages .rpm installed on your Red Hat / Fedora installation, use:

rpm -qa > installed.txt
List all installed .rpm classified by name and architecture
rpm -qa --queryformat='%{NAME}\n' | sort -n > installed.txt

List all installed .rpm classified by name only

rpm -qa --queryformat='%{SIZE} %{NAME}\n' | sort -n > installed.txt 
List all installed .rpm classified by name and size

Here is a short overview of selected tools :

Development tools

yum groupinstall "Development Libraries"
yum groupinstall "Development Tools"
eclipse
android skd
bison
clang
emacs
geany
bluefish
kompozer
amaya
dart
android sdk adt bundle
intel xdk
maven
gedit

Web Server

apache httpd
apache tomcat
mysql
postGre SQL
php
phpadmin
java
webmin
yum groupinstall "Server Configuration Tools"

Internet exploration

firefox
firefox add ons
-web developper
-noscript
-ghostery
-flash video downloader
chrome
vidalia tor

Network

wireshark
etherape
nmap

Communication

skype
empathy
pigdin
evolution
enigmail
gwibber microblogging
transmission
KMLdonkey
azureus
streamripper

Multimedia

cheese (camera effects)
blender (3D)
openscad (3D)
gimp
inkscape
pitivi
openshot
audacity
libreoffice
audacity
scribus (pdf)
texmacs (Latex)
lyx (Latex)
kile (Latex)
gtkpod (mp3)
mythtv
xmbc
minitube

System utils

kate
hardinfo
gpsd
ntpd
qt
qemu
openvpn
uget
postfix
steam
wine
clamav
java
open jdk
ruby
grip (DVD)
sound-juicer (DVD)

Security

ddrescue
gparted
testdisk
srm (secure file remover)
nwipe
firstaidkit-gui
xmount
pdfcrack
hfsutils (for HFS apple)
macchanger
ngrep
ihorsst
weplab
whois
dnsenum
openvas-scanner
hexedit
dnstop
dnstracer
iftop
ntop
trafshow
john
medusa
hydra
tcpdump
ssldump
etherape
stat (show file access rights as numeric codes ex. 777 instead of RWX)
libcurl
vlogger
webalizer
awstats
metasploit
nikto security scanner
putty




Commentars are open if you have better selection in each category ! 

Best Linux Tools for Mathematics, Scientific calculations, Algebra and Graphs

Mathematics with Linux are very interesting. Below is an overview of main programs for calculation, algebra, and graphs for scientific applications. These programs run on Red Hat Fedora and other Linux branches : Ubuntu / Mint / Arch / Suse / CentOS / Debian / Knoppix

Scientific Calculation

R A language for statistical computing and graphics (R-core)

rkward IDE/GUI for the R-project

calctool A multi-GUI (terminal, X, XView) calculator program

Sage. It's basically a Mathematica/Maple replacement.

Maxima Symbolic mathematics program. like Maple and Mathematica (maxima-gui wxMaxima)

octave High-level interactive language for numerical computations clone of Matlab

octave-forge Many additional features to math/octave

rascal The Advanced Scientific CALculator

scigraphica A scientific application for data analysis and technical graphics

scilab A free Matlab clone by INRIA & ENPC

petsc Portable, Extensible Toolkit for Scientific computation Portable, Extensible Toolkit for Scientific computation Portable, Extensible Toolkit for Scientific computation

sage sagemath basically a Mathematica/Maple replacement.

gsl GNU Scientific Library http://www.gnu.org/s/gsl/

SpeedCrunch Fast, high precision and powerful desktop calculato http://speedcrunch.org/en_US/index.html

mathomatic computer Algebra system (CAS) and calculator

Root Data Analysis http://root.cern.ch/drupal/

Graphing-Plotting

biggles Create publication-quality 2D scientific plots

linux-dislin A scientific data plotting package

ngraph A XY plotting tool for students, scientists and engineers

qscanplot A program to extract data from scanned plots, graphs and figures

lybniz Mathematical function graph plotter

matplotlib Python plotting library http://matplotlib.sourceforge.net/

GGobi Data Visualization http://www.ggobi.org/

G3DATA Extracting data from graphs http://www.frantz.fi/software/g3data.php

gnuplot graphing tool

grace WYSIWYG tool to make two-dimensional plots of numerical data

Diverses

py-gato A Python-based toolbox to visualise algorithms on graphs

py-gnuplot Python interface to gnuplot plotting program

py-gsl Python interface to GNU Scientific Library

py-numeric The Numeric Extension to Python

py-numeric17 The Numeric Extension to Python

py-probstat Probability And Statistics Utils for Python

py-scientific Collection of Python modules for scientific computing

SciPy Scientific tools for Python http://www.scipy.org/

Spyder Scientific PYthon Development EnviRonment http://packages.python.org/spyder/

Units

GNU Units Scale converter http://www.gnu.org/s/units/

top best Linux tools collection for electronic systems engineering

These tools are a selection of the best free tools for electronic engineering desktops on Linux. Especially they are working on Red Hat Fedora but might also be compatible with other Linux versions :  Ubuntu / Mint / Suse / Arch Linux / CentOS. ...etc

SELECTION FROM AUGUST 2014 

LabPlot	LabPlot is for scientific 2D and 3D data and function plotting. The various display and analysis functions are explained in the handbook (KDE help center). LabPlot also provides a component for easily viewing the project files in Konqueror.
alliance	Alliance is a complete set of free CAD tools and portable libraries for VLSI design. It includes a VHDL compiler and simulator, logic synthesis tools, and automatic place and route tools. A complete set of portable CMOS libraries is provided, including a RAM generator, a ROM generator and a data-path compiler. Alliance is the result of more than ten years effort spent at ASIM department of LIP6 laboratory of the Pierre et Marie Curie University (Paris VI, France). Alliance has been used for research projects such as the 875 000 transistors StaCS superscalar microprocessor and 400 000 transistors IEEE Gigabit HSL Router. You are kindly requested to mention " Designed with alliance (c) LIP6, Université Pierre et Marie Curie" so as to spread the word about "alliance CAD system" and its development team. Alliance provides CAD tools covering most of all the digital design flow: VHDL Compilation and Simulation Model checking and formal proof RTL and Logic synthesis Data-Path compilation Macro-cells generation Place and route Layout edition Netlist extraction and verification Design rules checking alliance is listed among Fedora Electronic Lab (FEL) packages.
electric	Electric is a sophisticated electrical CAD system that can handle many forms of circuit design, including custom IC layout (ASICs), schematic drawing, hardware description language specifications, and electro-mechanical hybrid layout.
fped	fped is an editor that allows the interactive creation of footprints of electronic components. Footprint definitions are stored in a text format that resembles a programming language. The language is constrained such that anything that can be expressed in the textual definition also has a straightforward equivalent operation that can be performed through the GUI.
freehdl	A project to develop a free, open source, GPL'ed VHDL simulator for Linux.
geda-docs geda-examples geda-gschem geda-symbols geda-utils	gEDA project. full GPL'd suite and toolkit of Electronic Design Automation tools. These tools are used for electrical circuit design, schematic capture, simulation, prototyping, and production. Currently, the gEDA project offers a mature suite of free software applications for electronics design, including schematic capture, attribute management, bill of materials (BOM) generation, netlisting into over 20 netlist formats, analog and digital simulation, and printed circuit board (PCB) layout.
gerbv	Gerber Viewer (gerbv) is a viewer for Gerber files. Gerber files are generated from PCB CAD system and sent to PCB manufacturers as basis for the manufacturing process. The standard supported by gerbv is RS-274X. gerbv also supports drill files. The format supported are known under names as NC-drill or Excellon. The format is a bit undefined and different EDA-vendors implement it different. gerbv is listed among Fedora Electronic Lab (FEL) packages.
ghdl	GHDL is a VHDL simulator, using the GCC technology. VHDL is a language standardized by the IEEE, intended for developing electronic systems. GHDL implements the VHDL language according to the IEEE 1076-1987 or the IEEE 1076-1993 standard. It compiles VHDL files and creates a binary that simulates (or executes) your design. GHDL does not do synthesis: it cannot translate your design into a netlist. Since GHDL is a compiler (i.e., it generates object files), you can call functions or procedures written in a foreign language, such as C, C++, or Ada95.
gnuradio	GNU Radio is a collection of software that when combined with minimal hardware, allows the construction of radios where the actual waveforms transmitted and received are defined by software. What this means is that it turns the digital modulation schemes used in today's high performance wireless devices into software problems.
kicad	Kicad is an EDA software to design electronic schematic diagrams and printed circuit board artwork up to 16 layers. Kicad is a set of four softwares and a project manager: - Eeschema: schematic entry - Pcbnew: board editor - Gerbview: GERBER viewer (photoplotter documents) - Cvpcb: footprint selector for components used in the circuit design - Kicad: project manager
rfdump	RFDump is a tool to detect RFID-Tags and show their meta information: Tag ID, Tag Type, manufacturer etc. The user data memory of a tag can be displayed and modified using either a Hex or an ASCII editor. Tag contents can be stored and loaded using a specific XML fomrat. This effectively allows to copy data from one tag to another. In addition, the integrated cookie feature demonstrates how easy it is for a company to abuse RFID technology to spy on their customers. RFDump works with the ACG Multi-Tag Reader or similar card reader hardware.
tetex-IEEEtran	The IEEEtran class is the official LaTeX class for authors of the Institute of Electrical and Electronics Engineers (IEEE) transactions journals and conferences.
xcircuit	Xcircuit is a general-purpose drawing program and also a specific-purpose CAD program for circuit schematic drawing and schematic capture.

HP The Machine new supercomputer monster for big datas

The Machine from HP Labs is a major disruptive technology innovation. Capable of adressing 160 petabytes in 250 nanoseconds, the machine uses photoelectornics with ions storage capability on memristors and a optic fiber connection between memory and processor. The Machine should run on open source software stack and non volatile android operating system version are already in development. This is a revolution in computing ! Great HP Labs. The Machine should be commercialized from 2018.

Visualizing the Internet in Real Time - a tool for BIg Datas by Akamai Technologies

The tools offered by Akamai to measure the Internet are quite interesting, notably they have stats about number of users, number of sites, network connections, attacks/viruses, network performance and are using some visualisation framworks to make the datas more friendly.

Anatomy of Linux computers : the File System Commands - part 1 ls

A- How are organized files in Linux ? 

If we examine the root file system of a typical linux fedora system, the Linux file system uses the command "ls" for showing file content . Running it as root, we get the following results :

root@localhost /# ls
bin   dev  home  lib64       media  opt    run   srv  tmp  var
boot  etc  lib   lost+found  mnt    proc  root  sbin  sys  usr

The file system is organized in sections : 

 
    /bin Essential user command binaries (for use by all users)

    /boot Static files of the boot loader, only used at system startup 

    /dev Device files, links to your hardware devices like /dev/sound, /dev/input

    /etc Host-specific system configuration 

    /home User home directories. This is where you save your personal files 

    /lib Essential shared libraries and kernel modules

    /mnt Mount point for a temporarily mounted filesystem like /mnt/cdrom

    /opt Add-on application software packages

    /usr /usr is the second major section of the filesystem. /usr is shareable, read-only data. 

    /var contains variable data files. This includes spool directories and files, administrative and logging data, and transient and temporary files. 

    /proc System information stored in memory mirrored as file

1. INODES

in order to show the inodes associated with the files, we must use the -i option : the inodes are associated registries associated with each file containing some metadatas. Inodes stands for Index Nodes. There is an inode number for each file. For example inode=5829 for the directory bin. In POSIX and partially POSIX-compliant operating systems, such as GNU/Linux, Android, Apple's Mac OS X, Windows NT operating systems, an inode contains information about : 
- the size of the file in bytes, in blocks and IO blocks
- the devicesID, inodeID, Links (how many hard links are pointing to the inode, an hard link) and timestamps last accessed last modified for each UID UserID and GID Group ID. The stat system call retrieves a file's inode number and some of the information in the inode.

root@localhost /# ls -i
   5829 bin        17 lib         1835009 opt        13 sbin   786433 var
      2 boot       16 lib64             1 proc  1179649 srv
   1025 dev        11 lost+found     3267 q           1 sys
1310721 etc   1966081 media       1703937 root     8070 tmp
      2 home  1048577 mnt            1159 run   2883585 usr

root@localhost /# stat boot
  File: ‘boot’
  Size: 1024       Blocks: 4          IO Block: 1024   directory
Device: 801h/2049d Inode: 2           Links: 4
Access: (0555/dr-xr-xr-x)  Uid: (    0/    root)   Gid: (    0/    root)
Access: 2014-05-11 15:39:55.000000000 +0200
Modify: 2014-01-09 03:12:33.000000000 +0100
Change: 2014-01-09 03:12:33.000000000 +0100
 Birth: -

1. ACCESS RIGHTS

in order to show the access rights, ls must be used with -l 

root@localhost /# ls -l /etc
total 2936
drwxr-xr-x.  3 root root     4096 25. Aug 2013  abrt
-rw-r--r--   1 root root       47 16. Mär 21:15 adjtime
drwxr-xr-x   2 root root     4096  7. Okt 2013  akonadi
-rw-r--r--.  1 root root     1518  7. Jun 2013  aliases
-rw-r-----.  1 root smmsp   12288 19. Aug 2013  aliases.db
drwxr-xr-x.  2 root root     4096 25. Aug 2013  alsa
drwxr-xr-x.  2 root root     4096 16. Apr 23:07 alternatives

...

root@localhost /# ls --scontext
system_u:object_r:bin_t:s0       bin -> usr/bin
system_u:object_r:boot_t:s0      boot
?                                dev
system_u:object_r:etc_t:s0       etc
system_u:object_r:home_root_t:s0 home
system_u:object_r:lib_t:s0       lib -> usr/lib
system_u:object_r:lib_t:s0       lib64 -> usr/lib64
...

for more information about the ls command and the basic structure of a linux system

NAME
       ls - list directory contents

SYNOPSIS
       ls [OPTION]... [FILE]...

DESCRIPTION
       List  information  about  the FILEs (the current directory by default).
       Sort entries alphabetically if none of -cftuvSUX nor --sort  is  speci‐
       fied.

       Mandatory  arguments  to  long  options are mandatory for short options
       too.

       -a, --all
              do not ignore entries starting with .

       -A, --almost-all
              do not list implied . and ..

       --author
              with -l, print the author of each file

       -b, --escape
              print C-style escapes for nongraphic characters

       --block-size=SIZE
              scale   sizes   by   SIZE   before   printing    them.     E.g.,
              '--block-size=M'  prints sizes in units of 1,048,576 bytes.  See
              SIZE format below.

       -B, --ignore-backups
              do not list implied entries ending with ~

       -c     with -lt: sort by, and show, ctime (time of last modification of
              file  status  information)  with -l: show ctime and sort by name
              otherwise: sort by ctime, newest first

       -C     list entries by columns

       --color[=WHEN]
              colorize the output.   WHEN  defaults  to  'always'  or  can  be
              'never' or 'auto'.  More info below

       -d, --directory

              list  directory entries instead of contents, and do not derefer‐

              ence symbolic links

       -D, --dired

              generate output designed for Emacs' dired mode

       -f     do not sort, enable -aU, disable -ls --color

       -F, --classify

              append indicator (one of */=>@|) to entries

       --file-type

              likewise, except do not append '*'

       --format=WORD

              across -x, commas -m, horizontal -x, long -l, single-column  -1,

              verbose -l, vertical -C

       --full-time

              like -l --time-style=full-iso

       -g     like -l, but do not list owner

       --group-directories-first

              group directories before files.

              augment  with  a  --sort option, but any use of --sort=none (-U)

              disables grouping

       -G, --no-group

              in a long listing, don't print group names

       -h, --human-readable

              with -l, print sizes in human readable format (e.g., 1K 234M 2G)

       --si   likewise, but use powers of 1000 not 1024

       -H, --dereference-command-line

              follow symbolic links listed on the command line

       --dereference-command-line-symlink-to-dir

             follow each command line symbolic link that points to  a  direc‐

              tory

       --hide=PATTERN

              do  not  list implied entries matching shell PATTERN (overridden

              by -a or -A)

       --indicator-style=WORD

              append indicator with style WORD to entry names: none (default),

              slash (-p), file-type (--file-type), classify (-F)

       -i, --inode

              print the index number of each file

       -I, --ignore=PATTERN

              do not list implied entries matching shell PATTERN

       -k, --kibibytes

              use 1024-byte blocks

       -l     use a long listing format

       -L, --dereference

              when showing file information for a symbolic link, show informa‐

              tion for the file the link references rather than for  the  link

              itself

       -m     fill width with a comma separated list of entries

       -n, --numeric-uid-gid

              like -l, but list numeric user and group IDs

       -N, --literal

              print  raw entry names (don't treat e.g. control characters spe‐

              cially)

       -o     like -l, but do not list group information

       -p, --indicator-style=slash

              append / indicator to directories

-q, --hide-control-chars

              print ? instead of non graphic characters

       --show-control-chars

              show non graphic characters as-is  (default  unless  program  is

              'ls' and output is a terminal)

       -Q, --quote-name

              enclose entry names in double quotes

       --quoting-style=WORD

              use  quoting style WORD for entry names: literal, locale, shell,

              shell-always, c, escape

       -r, --reverse

              reverse order while sorting

       -R, --recursive

              list subdirectories recursively

       -s, --size

              print the allocated size of each file, in blocks

       -S     sort by file size

       --sort=WORD

              sort by WORD instead of name: none -U, extension  -X,  size  -S,

              time -t, version -v

       --time=WORD

              with  -l,  show time as WORD instead of modification time: atime

              -u, access -u, use -u, ctime -c, or  status  -c;  use  specified

              time as sort key if --sort=time

       --time-style=STYLE

              with  -l, show times using style STYLE: full-iso, long-iso, iso,

              locale, +FORMAT.  FORMAT is interpreted like 'date';  if  FORMAT

              is  FORMAT1<newline>FORMAT2, FORMAT1 applies to non-recent files

              and FORMAT2 to recent files; if STYLE is prefixed with 'posix-',

              STYLE takes effect only outside the POSIX locale

       -t     sort by modification time, newest first

      -T, --tabsize=COLS

              assume tab stops at each COLS instead of 8

       -u     with  -lt:  sort  by, and show, access time with -l: show access

              time and sort by name otherwise: sort by access time

       -U     do not sort; list entries in directory order

       -v     natural sort of (version) numbers within text

       -w, --width=COLS

              assume screen width instead of current value

       -x     list entries by lines instead of by columns

       -X     sort alphabetically by entry extension

       -1     list one file per line

SELinux options:

       --lcontext

              Display security context.   Enable -l. Lines  will  probably  be

              too wide for most displays.

       -Z, --context

              Display  security context so it fits on most displays.  Displays

              only mode, user, group, security context and file name.

       --scontext

              Display only security context and file name.

       --help display this help and exit

       --version

              output version information and exit

       SIZE is an integer and optional unit (example:  10M  is  10*1024*1024).

       Units  are K, M, G, T, P, E, Z, Y (powers of 1024) or KB, MB, ... (pow‐

       ers of 1000).

       Using color to distinguish file types is disabled both by  default  and

       with  --color=never.  With --color=auto, ls emits color codes only when

       standard output is connected to a terminal.  The LS_COLORS  environment

       variable can change the settings.  Use the dircolors command to set it.

   Exit status:

       0      if OK,

       1      if minor problems (e.g., cannot access subdirectory),

       2      if serious trouble (e.g., cannot access command-line argument).

AUTHORS

       Written by Richard M. Stallman and David MacKenzie.

GOOG why the google stocks have decreased by 50 percents ?

When we look the recent crackdown of google, which value cours in GOOG action cotated at the Nasdaq 28 March at 1120.150$ lost 50 percents and finally founds 543.140$ on the 4th April 2014. we can explain this dilution by a spin off GOOGL

Spin off Date 04/03/2014
Security Type Equities
Parent Company Symbol GOOGL
Parent Company Price Per Share $1,135.10
New Company Security Type Equities
New Company Symbol GOOG
Percent of Cost Allocated 0.499229 (Not the Final Number)
Allocate Value the Same as Cost Basis Unchecked
New Company Price per Share $569.85
Share Distribution Ratio 1.0
Conversion Price for Cash in Lieu For Fractional Shares N/A

Neuromorphic Computing is coming up with IBM Synapse, Neurogrid and the US Brain Project

  In the emerging field of neuromorphic engineering, the neuromorphic computer is soon to be industrialized given an interesting Georgia Tech roadmap for developping neuromimetic devices.

Neuromimetic devices are analog information treatment, memorization and communication systems repeating the human cognition : a neuromorphic computer, having special electrical power requirements, is made of an integrated circuit with biological based neurons structures made of silicon and a FPAA for Field Programmable Analog Array, that permits to use the computing device.

Like field programmable gate arrays (FPGA), whiches are digital integrated circuits that are nearly ubiquitous in modern computing, the FPAA can be reconfigured by reprogramming it ("field-programmable."). There are scalable and we can forsee large-scale neuromorphic systems based on neuro mimetics, openning new frontiers in robotics and computing. To make cognitive applications easier to build and to help create an ecosystem of application developers, the team has created composable, scalable software cores called corelets.

Stanford scientists (including Krishna Shenoy, an electrical engineering professor at Stanford and Boahen's neighbor at the interdisciplinary Bio-X center), have recently developed microchips 9,000 times faster than a normal PC: Neurogrid, a circuit board consists of 16 custom-designed "Neurocore" chips, which can simulate 1 million neurons and billions of synaptic connections. 

When we look the U.S. BRAIN Project – (Brain Research through Advancing Innovative Neurotechnologies), two projects comparable to Neurogrid are particularly interesting :

* IBM's SyNAPSE Project (Systems of Neuromorphic Adaptive Plastic Scalable Electronics) has developped a chip code-named Golden Gate, to emulate neurons establishing communication with synaptic connections on the fly. At present a Golden Gate chip consists of 256 digital neurons.

* Heidelberg University's BrainScales project is developing analog neuromimetic mini network chips called HICANN (High Input Count Analog Neural Network). At present, the HICANN system can emulate 512 neurons 

Facebook invest acquires Oculus Rift VR company in Virtual Reality for $2 billions

Facebook new deal is the acquisition of Oculus Rift VR firm which produces a type of virtual reality (VR) glasses and 3D virtual reality augmented glasses as we can see on the video from Oculus Rift Development Kit. 

Oculus Rift started financement with Kickstarter and was bought by Facebook $400 million cash and 23.1 million Facebook shares, plus another $300 million in potential bonuses, announced the purchase via a blog post.

Mark Zuckerberg defined VR as the "next major computing platform after mobile"


Oculus Rift is similar to the project from SONY called Project Morpheus, the new PlayStation 4 VR headset, have been already described superior to Oculus Rift. 

4x4 Android Development Programming the First App

an App or Android application package file (APK) .apk is a javacode compiled by Android SDK Tools with datas and ressources files. The MIME type associated with APK file is application/vnd.android.package-archive

Below is a summary of programming the first application on Android, just after having created MyFirstApp from Google. 4x4 principle : 4 points for 4 code-components famillies.

1. The principle of functionment and organization of apps population into Android is based on the model of security-sandbox where : 
-Each app is runned by a linux user with a unique userID following principle of least privileges
-Each process runs on a Darrick VM
-Requests to user datas are granted on install 
-Any app can theoretically start another app components and instantiate their classes

2.App components types : there are only 4 types

ACTIVITY
SERVICE
PROVIDER
RECEIVER

Activities are screens : StartActivity(Intent)
Services : Startservice(intent), Bindservice (intent)
Providers of content: eg contacts with Content Resolvers
Brodcast receiver (eg low battery, download finished, call for activities) : Intent Objects : sendbroadcast (intent)

3. Manifest : android manifest.xml
defines permissions
api level
hw, sw, features needed : defines screen sizes, imput configuration (user-configuration) device features (user-features)
API librairies : eg. google maps API
declaration of Components :

 ACTIVITY 
 SERVICE 
 PROVIDER
 RECEIVER

4. Ressources
example : logo.png in Res/drawable having a RESSOURCEID in compiled code.