GL2 image files are related to Hewlett-Packard (HP) plotters and printers. GL2 files store data in HPGL printer control language format.

Newer HP devices not support GL2 files. However, many older devices still in use support this format. GL2 format is similar in form and use to HPGL and HPGL2 formats. Some image viewers (for example, XnView) offer the option to convert GL2 file to other formats.