Mathematica program details
Get familiar with the list of file extensions supported by Mathematica. By means of the mentioned application you will be able to perform at least the basic operations related with the listed files, such us opening, change or saving the file.
If you want to download Mathematica, you can use the link "Visit the website". The address leads to the producer of Mathematica. Such a trusted website is the safest and the most trusted source allowing to download the files for installation of Mathematica.