How are animations done in games?

Question

C++ / C#

Another so often pop-up question about game animation. I will not take time to say I will say I am a cyclist.
So what are the formats with animation support? Preferably the simplest and well-documented.
Where can I read about frame animation and skeletal animation? With simple examples and no extra water!
A big request in Russian, English at the initial level of reading help.
Also, if there are any other approaches for creating animation and lessons, articles on them, please share them. In general, tell me where to dig a person.
Ps I use c++ qt , openGl.

spoiler: Offtopic looking for where to download the book

opengl es 3.0. руководство разработчика на русском. В маем городе не продается под заказ дорого и долго. Поиск привел к версиям без перевода.

Answer 1

The most common is frame-by-frame.
Just like in cartoons.
Animation-enabled formats are not needed.
Since if the animation is associated with certain actions, then the frames should change not at random, but according to a certain logic.
If the frames should simply be replaced in a row, a looped video is quite enough.
But most often they use just one large file, in which frames are interspersed.

Answer 2

In addition to frame-by-frame animation, there is also skeletal animation.
Spine
Dragon Bones