Basically, a non-firing gun, which could be for a number of purposes. In countries with restrictive firearms laws, replicas may be the only way for people to be able to collect firearms. There's the "rubber ducky" replicas, which are a training aid - they're often used in bayonet training, in order to avoid risking damage to actual service rifles. In some cases, a replica is a real gun which has been modified to ensure it cannot fire. In others, it may be made with a rubber or aluminum body, and use components of real firearms.
These replica guns are also a great for antique collectors who cannot afford to buy a real gun, so at least they can have a gun in the form of replica. But beware of converting them to real guns as this is the illegal work to do.
You can dry fire a "REPLICA" gun if the action will allow. Some "REPLICA" guns will not have a true action and therefore cannot be fired. NEVER try to load live ammunition in a "REPLICA" gun.
Non firing replica
yes
no
Try google
No, you do not.
Laws on this vary by jurisdiction.
There are no permits required for paintball guns.
It's a copy of a gun/rifle that can't fire.
A collector would want the original. Sometimes (Most) the original is worth more than the replica.
Walther PPK, made famous by the early James Bond movies
A fake gun made to look just like a real one.