In addition to the program code to be executed, a nuBASIC program can also contain comments that explain the individual parts of the program and provide important information that can be helpful at a later point.

nuBASIC provides two methods for inserting comments in the program code:

All characters that follow an apostrophe are treated as comments: 

Dim A(10) : ' This is a comment for array A

The keyword Rem, followed by the comment:

Rem This comment is introduced by the keyword Rem

A comment includes all characters up to the end of the line.