First, skins to minecraft is just a cosmetic character change. They do not change the gameplay, but only the standard character for another, depending on the mask that the player chooses.
On the Internet there are many web resources where you can find skins for minecraf. First of all, these are sites with Minecraft mods (there is no need to call these web resources, there are a lot of them) There are also separate sites with masks. Also in some resources they are offered in HD quality. To create your own skins there are separate sites. Anyone can find them on the Internet.
Some gamers prefer to play with the standard skin. However, such people are so few that their number can be neglected. Conclusions - skins are a good way to stand out among other players. But not all Minecraft players are aware that there are many resources, and they only play with regular skins. No, this does not mean that the skin must necessarily be - this is the choice of each player. But do not forget that there is an opportunity to create your own personal guise, which will be different from others and will perfectly stand out among ordinary Internet skins.
It is also worth noting that the masks are very useful for finding a friend on the server. Especially if he has his own skin that his friend knows.
Now - how to install the skin. There is nothing difficult. You only need to find the nickname with the skin. The essence of this method is that there is no need to scale the game files - you just need to enter a certain nickname, when entering the game, and the mask will be changed.