Contacting a professor in the university you are applying I am applying to American universities. And just like many others, I intend to apply to many of them.

Anyway, I read a lot on the internet about this application thing and I notice that I should contact a relevant professor, read some of his articles and form an opinion (like in the answer of How does the admissions process work for Ph.D. programs in the US, particularly for weak or borderline students? ), maybe for the professor to acknowledge who this applicant (me) is.

I think there would be a big obstacle. Let's say I am applying to 10 universities, then I have to contact 10 professors. Their work may belong to the same big branch, but definitely to small branches. What I want to say here is, 10 articles in technically 10 different areas, and they are totally not easy to understand. Then it would be literally impossible to do such a task.

I really hope I took it the wrong way somewhere. Do I understand this "contacting professors" part? Hope you could answer me
Only contact professors if you are genuinely interested in working with them and can demonstrate that you might be a good fit. Profs get a lot of generic cold emails so it isn't worth it if you aren't excited about them specifically.

But if you see someone's work that really does interest you, then definitely reach out! In a short email, use a few sentences to demonstrate that you are interested, know what they actually do (take a look at a few of their papers), and why you are a good fit (relate your experiences to their work).