Why 3?
Having read through 5 pages of nearly identical suggestions, varying mostly in specific model or caliber, along with a few rediculous suggestions as "must own", here's my opinion.
For "must own" handguns (upper limit 3, although I have no idea why), they would be
1) a .22LR
2) a centerfire revolver
3) a centerfire semiautomatic
I have phrased it this way because for someone getting into handgun ownership, any make and model of each category is sufficient to educate the new handgunner on basic operating and safety principles, and particularly the .22 (in what ever action style preferred) allows for the cheapest, easiest training and practice.
The low cost ammo, low recoil and muzzle blast of a .22 pistol allows beginners to get familiar, and develope needed skills without the cost and risks of larger calibers. Being able to fire 500 shots in practice for the cost of 50 (or even 20) larger caliber rounds is benefical to the beginner, and experienced shooters alike.
Note that I said nothing about specific calibers, makes and models, beyond the .22LR, because I don't feel any specific centerfire gun, barrel length, & caliber belongs on a must own list.
The guns you
must own (as a begininer) are the ones that you will learn on. )Ones that will teach you the raw basics of handgun shooting, and the differences in general type (revolver vs auto). Once you have learned the basics, you will develop likes and dislikes, and an awareness of what comes easily to you, and what you will have to work at to master.
Then, when you have some ideas about which calibers, sizes, styles and types will fill both your needs and wants, you can get something best suited for the specifics you want.
Or, you could wind up like me, spending decades collecting numerous handguns, each time being certain that it was one I
must own.....
1. A .22 revolver. I think the Ruger Bearcat would fit the bill for reliability (don't trust semi .22s b/c of rimfire duds).
As to this, you get duds in revolvers, too. The difference is, with a revolver, you can usually go on and shoot the rest of the rounds, then take care of the dud. With an auto, you must take care of the dud in order to shoot the rest of the rounds!