No one answer possible. It will be a caliber with the best stopping power that you can shoot well, and is 100.00000% reliable. For some people, that is a .327 magnum, for some, a .45 ACP. I personally carry either a .357 Magnum or a compact .45 ACP, but both have too much recoil for my wife- who does very well with a .38 Special. As is often said- Your Mileage May Vary. Would suggest you visit a range that rents handguns for use on that range, and try as many as you can to see what works for you. A 250 lb football player and a 95 lb woman may have different needs and abilities- you did not say which one you were.
It all depends on you, your pocketbook, your skills.
Best to ask a gunsmith for help
There is no best gun because it depends on too many factors. The best gun for you is whichever gun that fits your hand the best so you can shoot it accurately. Beyond that, a gun for everyday carry must be reliable and be of an adequate caliber for self defense.
Can't be answered without knowing what caliber, intended use, make of firearm
There is no one single best caliber, but to get an answer, you need to be a little more specific. Rifle or handgun? Define long distance. 50 yards? 100 yards? 1000 yards?
Yes. Not the best choice, but yes.
Best is very subjective. Sig Sauer and H&K are among the best in general.
There is no "best caliber" because it depends on several things. If the child is new to shooting, a .22 is probably a good choice. They don't have much recoil, they are easy to shoot, and ammo is cheap. Many people start beginners on .22s.
Probably any small sized glock, all other good ones, Kimber, baretta, springfield are fairly large
Single shot 50 BMG Yes, that would work. You can shoot one with whatever handgun you wish to use. Just be sure you can run faster than whichever bear you pick to shoot if you pick a caliber that does not kill it.
Very likely, it's the Glock. Glock in general is the best selling pistol in the commercial and law enforcement market.
There is no best concealed handgun. There is a best concealed handgun for you! And, only you can be the judge of that. Size) Were on or about your body are you going to conceal the weapon? How big or small are you? Caliber) Find an instructor with access to a variety of guns in different calibers. Shoot 22 LR up to 44 mag and above if you choose. Determine what caliber best suits your physical and mental constitution. Style) Find an instructor with access to a variety of guns in different styles. Semi-auto, revolver, single action, double action, double action only etc. Pay attention to the different safety configurations. Determine what style handgun best matches your aptitude for mechanical complexiety. Once you can answer these questions, you can start shopping for a handgun. Once you obtain a gun practice regularly. After decades of experience with guns "my" best/regular carry gun is a glock 26. It is small, high capacity -13 rounds with extended magazine- decently potent caliber 9mm (particually with high performence JHP bullets) and completely reliable. 100% reliable in my case. I owned the gun since 1996 and never had a failure. In the end it is your choice. Do research and get practicle experience, eventually it will become completely obvious to you what the right best concealed Handgun for you will be. If you are going to ignore this advice and get a handgun anyway. I recomend any small framed SW revolver in 38 special. These revolvers are small, easy to shoot, completely reliable and "practically" idiot proof. Perhaps a Smith and Wesson 638. My second favorite concealed handgun and my wife primary concealed weapon.