The power of screen capturing
The fact that screencasting combines captured images and recorded audio to explain what is happening on screen makes it a very powerful medium to communicate knowledge and ideas. Screen capturing is used for demonstration of software features, for e-learning, for explanation how to use a given program in order to perform a particular task, for showing support personnel what is wrong with a given program, etc. Actually, only the author's imagination determines the limit of its applications.
Screencasting can be used both by companies and individuals. Although the best screen capture software packages are still very expensive (on average they cost $200-$300), there are low-price lite versions or completely free screen capture programs that are of acceptable quality and everybody can afford to create screencasts with them.
demo movies and tutorials
Probably companies are still the main group of screencasts creators. There are companies that have been recording screen movies for years to create demo movies and tutorials for their software. The purpose of demo movies is to show what features the software has. The purpose of tutorials is to make it easier to train users how to work with the program. While demo movies are more useful for sales and marketing purposes (to convince potential customers that the software is worth buying), training tutorials are valuable for existing customers and they do help to reduce the number of support calls from end users.
There are companies that specialize in creating demo movies and training tutorials on demand. Usually their offer is for creating professional looking (and sounding) screencasts where everything is fine-tuned to the last detail – the text is concise and easy to understand, the images are clear and the the visual effects are appealing, the voice of the narrator is pleasant to listen to and he or she speaks the language perfectly and clearly.
quick presentations
But if you want to make a screencast for a quick presentation in front of your colleagues or family, you will hardly need a demo of such quality. Instead, a short movie that you have done yourself in no time at all, can be quite suitable. Maybe you can go for a mute movie – if you are there to explain what is onscreen, there is no need to worry that your voice is harsh or you mispronounce certain words.
reporting software bugs
Screencasts are very useful when reporting software bugs or trying to explain that a program behaves strangely. A movie that shows what's going on the screen gives a much better idea about the problem than any textual description. Besides, often a bug appears occasionally only and even if it is described as fully as possible, if it cannot be reproduced and seen personally, it is unlikely that it will be fixed. So, by documenting bugs in a movie, you help developers to make better software.