What kind of Chinese? Mandarin?

Linguistically Chinese is not a language, but a family of languages that is united by a (mostly) common writing system. The reason that these Chinese languages are called "dialects" is mostly political.

A language geek I know, who taught himself various Chinese dialects and in particular Cantonese up to a very high level told me that Mandarin, though referred to as the "official" Chinese language that is used in TV, it is in his opinion rather an artificial language (he compared it with Esperanto).

So when learning some of the Chinese languages he recommended that at least after some time learning the ropes (writing system, tones, common words), one should really consider for what purpose one is learning Chinese and learn the appropriate language of the respective province (he was really into electronics, so he continued his study in particular into Cantonese).