See below for a list of popular unit testing frameworks and tools for major platforms and programming languages. These frameworks can be used by programmers to test specific functionality in libraries and applications. Unit tests can then be used to automatically test new versions and builds as part of an automated build system or deployment process.
I think we can all agree that automation is a critical part of any organization's software delivery pipeline, especially if you call yourself "agile." It's pretty intuitive that if you automate testing, your release cycles are going to get shorter. "So, if that's the case," you might say, "why don't we just automate everything?" There's a good reason: automation comes with a price.