How can i take a video of my computer screen?

You need a screen recorder program for Windows screen. If you type "screen recorder" to google, you get all what you wanted but I prefer Fast Stone Capture that is the most useful one around the word. Its trial time is 30 days so... but don't want to force you.

If you want to record games, you need another type of recording program such as Fraps.

It records raw video format so the quality is the highest. (but also slow on old pc-s)

In this case, I recommend another one like.. ZD Soft Game Recorder. Just type "game recorder".

Thats it.

Hit the print screen button on the keyboard. On laptops it is is own button (sometimes written as prnt scrn) and on desktop keyboards it is written on the front side of a key (one of the F1-14 keys). Then hit control - v (paste) when you're on word or photoshop or something like that. I've done it on word before and it works. Don't know about photoshop. Powerpoint should work fine as well.

Camstudio

Just download unregistered Hypercam 2 and if you can't get it to work on your pc then go to your desktop right click and click properties, go to settings, make color quality medium, then go to advanced. and go to troubleshoot and set hardware acceleration to none, but only if when you try to use hypercam and it says that yadda yadda pc something is too high and you can't record hope that helped :/

CamStudio, available at camstudio.org, is a free application for this.