In the initial part of this thesis, the reader will be introduced to a brief history of signal generators. The reader will learn the functions of the first signal generator, the year in which it was produced, and a brief introduction to the first commercial signal generator, General Radio 403. In the continuation of the paper will be explained the three most basic types of signals, their parameters, functions, and basic features. The reader will then be introduced to the designs of circuits that generate each of the previously mentioned types of signals or waves. The importance of that part of the final paper is the ways of changing the wave parameters. Below, the reader will learn about the main types of generators, and their advantages, and disadvantages. At the very end of the final paper, there is a conclusion in which the importance and widespread use of signal generators is emphasized once again.