Linux programs for screen capture
There are many screen capture options available for Linux users. Some of these are built in to the major distros by default. For instance in Ubuntu the PrtScrn key automatically captures the whole screen and activates the Gnome-Screen shot program. This displays the image in a small window and allows it to be saved and/or copied to the Clipboard. Gnome-Screen shot can also be called up from the Ubuntu menu system via Applications / Graphics / Take Screen shot. Using it like this allows the user to delay the screen shot for a few seconds if necessary – e.g. to bring other windows to the front. The Alt-PrtScrn key works the same way, but copies the currently open window, rather than the whole desktop.
Somewhat more powerful are the free screen capture programs KGrab and Ksnapshot. Which allow the user to select a rectangular region of the screen for capture. Both are designed for KDE systems as the names suggest, but I was able to use KSnapshot without difficulty on an Ubuntu installation (KGrab, however, gave me a black screen). In addition to the options mentioned above, both allow the user to set preferences as to where the screen shot will be saved and in what format, including TIFF, JPEG, PNG and Windows BMP. KSnapshot comes with a brief manual of instructions for use, but I was unable to view any documentation for KGrab.
Recordmydesktop is a Linux application which records activity taking place on the screen over a period of time. The user begins by providing a file name and selecting a portion of the screen then a small icon appears in the task bar at the top of the screen. Everything that occurs in the selected area is then recorded and when the user clicks the icon in resulting animation is saved as an OGV file under the name given. A graphical front end GTK-Recordmydesktop, allows users to operate the program graphically. When this is installed it will be found in the Applications / Sound & Video menu. I was unable to get it working on my system, however it crashed some other windows open on the same screen. So use it with caution!