What is a level 1 hurricane?

Yesterday we went drove around with Pete and Donna, going to a Senior Expo (it wasn't much), then out to lunch at JB Boondocks. Today we will get together for Mexican Train and a lasagna dinner at our place. But along with the fun is a pretty serious weather watch because a bad storm has been curling in from the gulf for a couple of days. That curl has formed it into a hurricane, and it's supposed to hit us today. At this point it's supposed to be a level 1 hurricane, and I don't know what a level 1 hurricane will be like. I guess we will see.