As mentioned previously, testing is an essential (yet often overlooked) component of software development specifically, and programming in general. The goal of testing is to evoke errors that would indicate the existence of bugs in our programs. This is to be contrasted with the process of debugging, which is used to identify the bugs themselves; we will discuss the topic of debugging in the next section.

In the most general sense, testing is about determining whether specific functions and methods can perform and produce results that we intend them to; this is typically done by comparing the results that are produced. In other words, testing is collecting evidence as to the correctness of our programs.

However, testing cannot ensure that all potential defects and bugs in the program under consideration will be identified. Additionally, the test...