Jing is a piece of free software for screencasting and screen capture. It can be downloaded for both Mac and PC from http://www.jingproject.com/.
Jing allows you to take a picture of anything on your screen. You can then annotate your still image and add objects like arrows.
Here is an example of what a Jing screen capture looks like.
You can also create a video of you doing something on your computer. The video captures the screen while you narrate what you are doing.
Here is an example of how Jing was used to create a video explaining how to insert clip art into a Word document.
When you have finished capturing either your still image or movie, you can choose to upload your image/movie to the Internet to share with others or simply save it to your computer as a SWF video (if you want to save files as MPEG4 format or upload to video sharing sites you need to pay a small yearly fee for Jing Pro)
Jing is a great way to make tutorials for your students, colleagues or friends! It is a much easier way to explain something than giving just verbal or written instructions and it is very easy to use!