We are a commune of inquiring, skeptical, politically centrist, capitalist, anglophile, traditionalist New England Yankee humans, humanoids, and animals with many interests beyond and above politics. Each of us has had a high-school education (or GED), but all had ADD so didn't pay attention very well, especially the dogs. Each one of us does "try my best to be just like I am," and none of us enjoys working for others, including for Maggie, from whom we receive neither a nickel nor a dime. Freedom from nags, cranks, government, do-gooders, control-freaks and idiots is all that we ask for.
A Pull-up is with overhand grip. The challenge is mostly to your upper back. You pull with your back while your arms mostly just hang on.
A Chin-up is with underhand grip. The challenge is primarily to arms and secondarily to upper back.
I shamefully still can not do enough reps of either to make for a worthwhile exercise, so I am practicing with jumping pull-ups, pull-ups with the band, and holds. Also, the pull-up machine sometimes.
If pull-ups and chin-ups are too easy for you, widen your grip or put on a weight vest.
My goal is 10 reps of each, but I may never get there. When I was in high school you had to do 10 or they put you in remedial phys ed which was basically an excellent sort of boot camp for 2 hrs/day. In fact, it was a lot like Crossfit with medicine balls, sprints, jumps, push-ups, 1-mile races, etc.