Free Softwares

Commercial Software	Similar Open source	Download Link	License	Used where
MATLAB	Scilab	http://www.scilab.org/products/scilab/download	CeCILL	Engineering (Electrical, Mechanical, Civil, Electronics, Embedded systems, Chemical), Science (Physics, Mathematics)
Mathematica	Maxima	http://maxima.sourceforge.net/download.html	GPL	Mathematics, Engineering
Cadence pSpice	ngspice	http://ngspice.sourceforge.net/download.html	BSD	Engineering (Electrical, Electronics, Embedded systems)
Microsoft Office	Open office	http://download.openoffice.org/	LGPL	All branches
Microsoft Office	LaTeX	http://www.latex‐project.org/ftp.html	LPPL	All branches
Mathematica/Maple	Sage	http://www.sagemath.org/download.html	GPL	Precise arithmetic, algebra, symbolic computation
Microsoft Windows	GNU/Linux	http://www.gnu.org/software/software.html	GPL	All branches
Turbo C	GCC	http://gcc.gnu.org/releases.html	GPL	Engineering (Introductory Computing – all branches)
Pro/E	BRL-CAD	http://brlcad.org/d/download	BSD	Engineering (CAD)
MASM	NASM, FASM	http://www.nasm.us/pub/nasm/releasebuilds http://flatassembler.net/download.php	BSD, BSD	Engineering (Electronics, Computer Science)
MS OFFICE Plotting tools	Xmgrace, XFIG, GNUPLOT	http://sourceforge.net/projects/graceplot/ http://xfig.org/art17.html http://www.gnuplot.info/download.html	BSD, GPL, Own license (but free)	Drawing the figures, plots, flow diagrams
Code composer Studio, IAR Workbench	GNU Binutils	http://ftp.gnu.org/gnu/binutils/	GPL	Assembler, Compilers for micro controllers and DSP Processors (MSP, VC33 etc)
VxWORKS	RTLinux, RTAI	http://www.faqs.org/docs/Linux‐HOWTO/RTLinux‐HOWTO.       html https://www.rtai.org/	GPL, GPL/LGPL (kernel and user space respectively),	Real-time operating System for Desktop and Embedded Systems
KEIL 8051	SDCC	http://sdcc.sourceforge.net/index.php#Download	GPL	GCC SDCC compiler for 8051 controlers
synopsis-CosmosSE, Mentor-Icstudio, Cadence-Virtuoso	Xcircuit	http://opencircuitdesign.com/xcircuit/download.html	GPL	schematic design
Mentor-ICstation, Cadence-Virtuoso	Magic	http://opencircuitdesign.com/magic/download.html	BSD	Used for chip Layout design
Modelsim	ghdl, freehdl	http://ghdl.free.fr/download.html                  http://freehdl.seul.org/	GPL	VHDL compiler
Matlab	Octave	http://www.gnu.org/software/octave/download.html	GPL	Numerical Computation
AutoCad	KiCad, FreeCad	http://kicad.sourceforge.net/wiki/Downloads http://sourceforge.net/projects/free‐cad/	GPL	CAD system
S-Plus	R	http://cran.r‐project.org/bin/	GPL	Statistics
Operating System	GNU/LINUX	http://www.bosslinux.in/	GPL	Operating System