Question marks

 

A question mark (?) comes at the end of a sentence which is asking a question.

Where are you?

What is your favourite colour?

 

http://www.oxforddictionaries.com/words/punctuation

Exclamation marks

An exclamation mark (!) comes at the end of an exclamation. It shows that the sentence is about something urgent or surprising, or shows anger.

It’s a goal!

An exclamation mark may also be used at the end of a command. A command is a sentence which gives an order or instruction

Stop it!

 

http://www.oxforddictionaries.com/words/punctuation