Rare skills

Question

Sometimes you see skills in learners profiles that are not linked to courses available on sololearn, such as arduino or raspberry pi. Actually I don't find them at all in the learn section

Answer 1

That's true, I think it's only for the profile details purpose.
So that other Sololearners can know about the person skills.
I think its for letting other Sololearners know about the person skills so that they can ask for help when they need it(especially in a specific language/technology which the person has included as his/her skill) .
BTW i just searched for "erlang" and it's logo pops up in the Skill section, cool! :)

Answer 2

Yeah, I know. But there are also "skills" that are not hardware related, such as bash/shell or Django. They are in the skills sections of some profiles and they use Sololearn style Icons. So I thought this comes/came from SL.
Other topics could be interesting, but I haven't found them so far, such as R or Assembler.