Is it normal to be working out sometimes and then u fell a crack in ur arm? lol. its weard like when u crack ur knuckles,i feel that in my arm sometimes then im working out...normally when i do pushups...But after the first crack or to it stops.

Anything cracking isn`t normal. But is it dangereous or not don`t know. For example my neck cracks like i`m breaking it.

Do you warm up enough?

As long as there is no pain involved, it should be ok.

My elbows crack all the time doing push ups.

Its nothing more than an "air bubble" popping

Same as when the knuckles pop, just on a slightly larger scale.

And from what I've gathered, no need to worry about getting arthritis either...at least not from that.

If it bothers you are causes pain or discomfort, best to see the doc about it.

My shoulder cracks like 15 times in a row when i strech it out or do light workouts to get the healing to speed up

Its not really bad, but not good either. Ideally you dont want to be cracking everytime you do something.

My back cracks ocassionaly when I stretch it.

Hya! I'm like a flipping xylaphone when I move about! Gym, TKD, house work, stretching....
I agree with the air bubble thing. My neck, back, shoulders, spine, hips, knees and ankles crack! Maybe I'm just an old chicken ha ha! When I go to my physio (when I can afford it!) He manipulates my body doing great big popping and cracking noises, he said that it is air in the muscles and joints. Hmmm. I think pain would be a sign of your body needing attention, or maybe you are abit tightened up in the "noisy" area. I don't know how medical systems and things work only in UK but I go straight to a chiropractor or physiotherapist for specialist advice and treatment. xxx

Any tingling, numbness when the popping happens? Any weakness when it pops? COold be absolutely nothing, but then again you could be popping the bone literally out of the joint, but that's pretty unlikely without meaningful sustained pain and impaired movement.

See a doctor... if it continues.

Its merely my opinion, I could surely be mistaken...
Jeff