tmux - tmux is a terminal multiplexer: it enables a number of terminals (or windows), each running a...

Greenshot - Greenshot is a free and open source screenshot tool that allows annotation and highlighting using the built-in image editor.

GNU Screen - Screen is a full-screen window manager that multiplexes a physical terminal between several...

Shutter - Shutter is a feature-rich screenshot program.

mtm - Perhaps the smallest useful terminal multiplexer in the world.

Snipping Tool - Use Snipping Tool to capture a screen shot, or snip, of any object on your screen, and then annotate, save, or share the image