This is a list of free application for screen capture that can be installed for free in your computer. Take into account that some of them have restrictions on their use (for example, you cannot use some of them for commercial purposes).
Requires admin authorization to be installed.
Requires admin authorization to be installed, but it can be extracted as a file and run.
iSpring Free Cam
Not for commercial use.
Platforms: Windows, Linux, Mac.
Java-based. Does not require installation, it is just a JAR file. Not very mature.
Open Broadcaster Software
Platform: Windows, Linux, Mac
Screencast Capture Lite