Blender is a 3D graphics application used for modelling and creating interactive 3D applications and games.
To install, download the correct package from the official Blender webpage. For Ubuntu (and all 32-bit Linux OS in general), do the following:
1. Download the package form here.
2. Save it anywhere, for example in a directory named Setup_Files in the home directory.
3. Open a terminal, and extract the .tar.bz2 file first.
varsha@varsha-laptop:~/Setup_Files$ tar -xvf blender-2.49b-linux-glibc236-py26-i386.tar.bz2
4. Now cd into the extracted folder, and run the blender executable file.
varsha@varsha-laptop:~/Setup_Files$ cd blender-2.49b-linux-glibc236-py26-i386/
Another simple alternative is:
varsha@varsha-laptop:~$ sudo apt-get install blender
Replace apt-get with the package manager of the distro you are using and install as a superuser.
That's all. Now enjoy creating your 3D application!