Raw. Why so sorry?

Question

Images

Hello!
I took photos and uploaded them via vk, as a result, in the ".thumbnails" folder, there were raw images that looked something like

this:

According to the idea, this is supposedly a "scheme" of compression produced either by programs or by the phone itself (the phone was: htc Legend with a bucket 2.2), etc.
Questions:
1) What is it?
2) And how to achieve the same cool effect on your own? So that the same thing happened in the images.
I attach the files themselves to make it easier to understand what is what:
rghost.ru/6NvH772LG

Answer 1

Well, it's thumbnails, once they are in the thumbnails.