Learn C org - Good Or Bad ??

C Programming ..

---

---

---

C programming is a effective skill in the market this I know for sure (From surveying the internet of course lol) .
Idk I mean everybody on the internet said learning the syntax and logics of C especially the "pointers" one :)

So after like half an hour of researching I got this website called learn-c.org which provides interactive tutorial on various functions and sections of the language ..

I mean I would obviously be buying books on C but first I wanted to know what exactly is this thing like I didn't want to make the mistake of buying wrong types of books ..
If anyone is reading this who is a programmer or does programming as a profession or is learning the C language could you please help with the books ??