What is proportional representation? How does it work?

I've googled it and the answers I'm getting are super lengthy, and hard to understand. If it helps, I am currently studying the Great Compromise/The Connecticut Plan of Govt.

Make it short, sweet, and to the point.
Thanks so much :)

Proportional representation means that there is one delegate for x amount of people. States with large populations get more delegates than those with smaller populations.