Software testing is a vast domain, but it can be thought of as two key buckets: automated testing and manual testing. Automated tests are run with scripts, enabling huge amounts of testing to be done rapidly. Like the name implies, manual testing is performed by individual, and is much slower.
Though these two approaches are different, each has its advantage and place in the QA world. This article from DZone summarizes how to measure and balance the value of both manual and automation testing.