This was something I used to ignore because I never really understood it. Yes I know it had to do with how big or how small your item would be but I didn't truly understand what it meant and why I should care. When I first started knitting over 30 some years ago, there was no YouTube or podcasts or anything like this that truly helped one get the grasp on gauge until the last number of years. You no longer have to go to the library to find a resource book in hopes to find what you are looking for. There are so many wonderful makers or knit crochet instructors that help share their knowledge, tips and tricks and the one that I would like to share about today is Brittany from Bhooked. She has a two part series on her podcast that you do not want to miss.
She has taken questions from her followers and answers them in a completely logical and understandable way. As you listen you realize that you get it finally.
Below I will add both links to this amazingly informative podcast, I promise you, its worth a listen.