TrueCrypt is an open source encryption software which allows you to keep your data and files safe and prevent them from unauthorised access.
To install TrueCrypt, first download the Linux version of TrueCrypt from here.
Make sure you select the .deb file from the dropdown menu. Once the download is complete you will see that the file is archived into a .tar.gz file. Right-click on the file and select “Extract Here”.
Once the .deb file has been extracted, double-click on it to start installation. Follow the installation steps on the screen until the setup is complete.
You can find TrueCrypt by going to Applications -> Others.