As refers to something or someone's appearance or function. Like has the meaning 'similar to' and is used when comparing things. For example: As your boss, I must warn you to be careful. (I am your boss) Like your boss, I must warn you to be careful. (I am not your boss, but I have similar attitude) Hope this helps!

There is an entire article about the word "like" and its use in English: Speak ‘Like’ an American: Formal and Informal Uses of ‘Like’ in the English Language http://www.italki.com/article/220/speak-like-an-american-formal-and-informal-uses-of-like-in-the-english-language

Like : We use it when the second term of the comparison is a noun, a gerund or a pronoun. Dave looks like his father. - Don't act like me ! Tolearnenglish is like having your own private tutor. Like can be modified with adverbs , such as : just, more, very much, not at all... : Just like you, Jane wanted to be a doctor. AS : We use it when the second term of the comparison is a verb, a clause or a preposition. Don't do as I do ! It started raining, as I said it would. Prices are very high, as in the 1990s. (as they were) As can be used before a noun: She works as a nurse.

Please word your question differently. I do not understand it. What's the difference between.... ????