Recently I needed to take a screenshot of my Raspberry Pi. I have done this before with a digital camera, but I found a nice little utility called scrot
This can be installed with sudo apt-get update followed by apt-get install scrot
The utilty is called from the command line in its simplest form by typing scrot which will take a screenshot immediately and store it in the current working directory.
If you want to take a picture of the graphics desktop the simplest way is to open an lxde terminal window and type scrot -d 5 Then minimise the terminal window and 5 seconds later the picture will be saved. The timestamp is included within the filename.
The program is actually capable of more sophisticated settings which are listed by typing scrot –help
You can for example take a screenshot of a window or region of the screen or include a border or generate a thumbnail of the image.
for example type scrot -d 5 -u -b in the terminal window then press return
click on a window with the mouse on the graphics screen and 5 seconds later a picture will be saved of this window alone with its border.
This is a great little utility