recently,i read lots of tutorials about color channels of photoshop.it's so hard.especially the channels count.

so could anyone gives me some tutorials of this,i have searched it,but only found out some acticles about LAB color channel.

and i also need some high-class tutorials about photograph style.i have read many good chinese tutorials about photograph style with chinese element.but there are many processes involving channel knowledge.so it's hard to understand....

so where can i find tutorials about channel count?can anybody recommends some websites or books to me(it would be better if the books can be downloaded.cos i am not sure weather i am able to buy it.)?

ps.cos i am not using a english version photoshop,so i am not sure weather this function is called "channel count".