What Is a Beta Reader?
Let’s start by laying out the differences between a beta reader and an editor. They perform a similar function, certainly, but they are very different kinds of readers.
An editor is a paid professional, typically with academic or professional credentials that qualify him or her to look at a piece of writing with a critical eye. An editor has the judgement and skills required to make (often extensive) changes to a story’s plot, character development, structure, and grammar without sacrificing its style or voice. For a comprehensive audit of your story, a professional editor is your best bet.
A beta reader, on the other hand, doesn’t necessarily have the same credentials. That’s not to say it’s never happened. In fact, it’s probably happened a lot. But typically, a beta reader is unpaid, and his or her feedback tends to be that of a casual reader or observer rather than a professional. To put things in perspective, your beta readers could be your neighbour, your co-worker’s brother, and your mom. (But it might be best not to rely on your mom for critique. She might have a hard time being honest. Or maybe not. You know your mom better than I do.)