Qemu 1.3.1 is a virtualization software and an emulator. A virtual machine allows you to install a guest operationg system on it and start testing software on the guest OS.
To install Qemu 1.3.1 on your Linux and Unix System, from sources, do the following:
Download Qemu from the official site with wget:
$ wget wiki.qemu-project.org/download/qemu-1.3.1.tar.bz2
Extract the archive:
$ tar -xjvf qemu*.tar.bz2
Create the makefile:
$ cd qemu-1.3.1
$ ./configure
Compile from sources:
$ sudo make
Install:
$ sudo make install
Clean the useless files that have been created with the compilation:
$ sudo make clean