How To Use A Colon

Using A Colon

• The two ubiquitous dots are placed after an independent idea, the idea is a promise and what follows the colon is the fulfilment of the promise. For example,Benjamin Franklin proclaimed the virtue of frugality: a penny saved is a penny earned. Or, another example would be, there was only one possible explanation: the milk had soured.
• When a list of items is to be mentioned, a colon can be used after the opening line. For example, the following chicken dishes were available: Grilled chicken, butter chicken, Thai chicken green curry and chilly chicken. Two things to be observed here are that, the word after colon is capitalised and there is a need to use the word ‘and’ before listing the last item on the list.
• A colon is can be used to introduce a quotation. So the next time you are adding a quote to an article, insert a colon. Just a reminder, the colon stays out of the quotation marks. For example, John F. Kennedy issued this stirring challenge: "Ask not what your country can do for you; ask what you can do for your country."  If the first part of the sentence is not a stand-alone thought then using a comma instead of a colon is correct. For example, John F. Kennedy said, “Ask not what your country can do for you; ask what you can do for your country."  
• A colon is used to lay emphasis on the point. Though two sentences can be made out of one by removing the colon from the main sentence but the emphasis is usually lost. For example, “The little boy of six was beaten badly. His crime: stealing a loaf of bread to feed his hungry sibling.”
• A play script or even a movie script has generous sprinkling of colon. For example, Doctor: You could face death if you don’t take the medicines regularly!
• A colon is used after the salutation statement in a formal or a business letter. For example, “Dear Dr. Robertson:”
• A colon is used in the opening lines to a formal speech. For example, “Honourable Chief Guest, Ladies and Gentleman:”
• A Colon is also used in memos. For example, “Date: 13.12.10; To: Margaret Johns; From: Jonathan Smith; Re: Permission for leave”
• When writing a ratio, using a colon between the numbers is the norm. If the ratio is written in words then it should be written like this, for example, four to one. Otherwise, 4:1.
• Colons are used in definitions. For example, Colon: "A marke of a sentence not fully ended which is made with two prickes."