While Ubuntu 16.04 offers the 6.3 release of the Racket language (formerly PLT Scheme), here’s the quick tutorial shows you how to install the most recent Racket 6.6 including DrRacket in Ubuntu 16.04 via PPA.
For the changes since Racket 6.3 to 6.6, see the official blog.
1. Add the Racket PPA
The software has an official Ubuntu PPA that so far offers the latest packages for Ubuntu 16.04, Ubuntu 16.10, Ubuntu 14.04, Ubuntu 12.04, and their derivatives, e.g., Linux Mint 17, 18.
To add the PPA, open terminal (Ctrl+Alt+T) and run command:
sudo add-apt-repository ppa:plt/racket
Type in your password (no visual feedback) when it prompts and hit Enter.
2. Once you have the official PPA repository enabled, upgrade Racket from a previous release via Software Updater:
Or just run command to install or upgrade the language platform in terminal:
sudo apt update && sudo apt install racket
Downgrade Racket (DrRacket):
You can restore the changes anytime by purging the PPA repository via ppa-purge command, which automatically downgrades the Racket version to the stock version (6.3 for 16.04) in Ubuntu main repositories:
sudo apt install ppa-purge && sudo ppa-purge ppa:plt/racket