EMOM means "every minute on the minute." At the top of each minute you start a fixed chunk of work, say 10 kettlebell swings, and whatever's left of the minute is your rest. Finish in 25 seconds, you rest 35. The clock repeats for a set number of minutes, and the format forces a steady, honest pace without you having to think about it.
Why it matters
Pacing is the hardest skill in conditioning, and EMOMs solve it with a clock. You can't blow up in minute two, because the work per minute is capped. You can't slack either, because the next round starts whether you're ready or not. That built-in structure makes EMOMs great for skill work too. Ten minutes of 3 crisp pull-ups per minute gives you 30 quality reps with fresh-enough form on every set. Way better practice than one ugly max set of 15.
How to use it in training
Pick work you can finish in 30 to 40 seconds when fresh. That leaves enough rest to keep quality high through the back half, which is the whole point.
For conditioning, try a 12 to 16 minute EMOM alternating two movements: odd minutes 12 calories on the rower, even minutes 10 burpees. For strength or skill, keep reps low, around 2 to 5, at a weight you could double. If you're still working at second 50, the load or rep count is too ambitious. Cut it. The format only teaches pacing when you can actually hold the pace.