Camtasia is one of the most widely used Video recording toosl on the market. In Internet Marketing it holds the prime place, because of the realative ease it brings to recoding and editing. You can make professional videos and voice overs for Powerpoint presentations with verry little training.

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TechSmith's New Camtasia Studio 8 Brings Professional Video Creation to the …

"OKEMOS, Mich., Jun 19, 2012 (BUSINESS WIRE) — For too long the world has been plagued by complicated video creation software that can take a lifetime for non-video professionals to master. With the launch of TechSmith's new Camtasia Studio 8, …"
http://www.marketwatch.com/story/techsmiths-new-camtasia-studio-8-brings-professional-video-creation-to-the-masses-2012-06-19

There are other options on the market, both free and paid for. For short videos you might want to consider Jing or Snagit from the same company. These, however,do not have the same editing capability. Corel also have a suite of products that can match the functionality and price of Camtasia. Another one to consider is a suite produced by an Australian Company, NCH.