Colons

Colons are used in the following ways:
Lists
Colons introduce a list.

• This is what I need from the market:  potatoes, eggs, and bread.
  

The list can't be a necessary part of the sentence.  This means
the sentence before the colon must be complete.

Incorrect:        

• Items I need from the market are:  potatoes, eggs, and bread.
  

 
Between Titles and Subtitles
Colons separate the main title from a subtitle.

• Lord of the Rings:  The Two Towers
  

Time
Colons separate the two parts of the time.

• 11:30, 12:15
  

Salutations
Colons are used after formal salutations in letters or e-mails.

• Dear Jonathan Malone:
  

Quotations
Colons are used to introduce a quotation.  This often includes
large quotations separated from the rest of the text.

• The United Nations made this statement regarding poverty:
  

      ``quotation.....``