Deads are about picking up heavy stuff, and putting it back on the floor. A basic functional effort and good training for how to pick things up without back strain.
They are demanding of every lever in your body. For men and women especially after age 40: Why deads belong in any fitness program: Deadlifts are important, and you should be doing them. Here’s why.
Good technique is essential. Do them wrong (eg lifting with your back istead of your legs) and you can hurt yourself. Do them right - it's not complicated - and your whole body gets stronger including your back. Deadlifts prevent aging! Mrs. BD does them weekly, and swears at by them.
Besides general fitness, just doing 5 sets (including a warm-up set) of heavy deads once-weekly has been great for my posture. Generally finishing with my 6-8-rep max. I only aim for a max one-rep effort every couple of months, just for fun (?). Since I am not a big strong guy, I can probably only get to around 300 with a trap bar at this point, and that is good enough for government work. With a plain bar, my grip tends to fail first. (I do need to work on my grip strength.)
Mens sana in corpore sano. (The former is a tougher challenge than the latter.)
(An important deadlift tip - and for barbell squats too - that is rarely mentioned: Make sure your bowels are well-emptied first. The intra-abdominal pressure gets high with heavy weights, and you do not want an accident. Farts are expected, but...)