ScreenSnag provides the basic tools for screen capturing. Whereas some may find it reliable and lightweight, more advanced users will probably feel disappointed because of the small number of functions the program can provide.
Intuitive enough to appeal even to beginners this tool will enable users to take a photo of the entire screen, only a selected region of the screen, a window or a small element. Activating it is a matter of a click or of a specified hotkey.
An advantage is the Timer function that captures the screen at pre-defined intervals. Any settings combination can be saved so that no further user intervention will be needed afterwards.