Most programming and markup languages support the notion of “comments”, or regions of code which are ignored by the compiler/interpreter. jEdit has commands which make inserting comments more convenient.

Comment strings are mode-specific, and some in some modes such as HTML different parts of a buffer can have different comment strings. For example, in HTML files, different comment strings are used for HTML text and inline JavaScript.

Edit>Source Code>Range Comment (shortcut: C+e C+c) encloses the selection with comment start and end strings, for example /* and */ in Java mode.

Edit>Source Code>Line Comment (shortcut: C+e C+k) inserts the line comment string, for example // in Java mode, at the start of each selected line.