COLON: THE PUNCTUATION





Unlike a semicolon, a colon is an undervalued piece of punctuation. It is often missed used or simply underused. We use it for six following reasons:
  1. Use it to introduce a list or series of examples.
  2. Use it to explain what precedes the colon.
  3. Use it to introduce a quotation.
  4. Use it to add emphasis to any explanation
  5. Use it to introduce bullet points 
  6. Use it in special circumstances ( conventional use)

Colon to Introduce a List
Let’s take a look using the colon for introducing a list.
I had several things on my mind:
In this example, we have one independent clause I have had several things on my mind before the colon. So the rule is that there is always an independent clause before the colon. We also have noticed that this independent clause is introductory. It is introducing something. After the colon is an explanation of what we introduced. So let’s look at this example.
I had several things on my mind: papers, grades, and finals.
We can ask a question about what those things are.
The answer is papers, grades, and finals.
So a list is formed after the colon and we use an independent clause before the list.
Note the introductory nature of the clause before the colon.
Take more examples.
I have several classes this term:  Math 110, English 400, and Online Teaching1000.
Even small rooftop gardens can produce a variety of vegetables:  beans, squash, tomatoes, and corn.

Colon between Independent Clause
In this usage, the independent clause after the colon ANSWER A QUESTION that could be posed about the first independent clause. In other words, we are going to introduce something then going to say something about it. 

Let’s look at an example.
My English instructor is wonderful: he makes punctuation fun and easy to learn. 
Here we have an independent clause My English instructor is wonderful. When we see the colon, we see that this independent clause is going to introduce something.  What is the question we can derive? Why my English instructor is wonderful?  Because he makes punctuation fun and easy to learn.
Here are more examples.
The river was dangerous:  the spring runoff had made it flood several towns.
Do not bother grandma while she’s baking: she will hit you with her broom!

Colon to Introduce a Quotation
In this use, the independent clause (s) after the colon is a QUOTATION.
Mr. Thompson went into great detail about how much he loves being a dog hairstylist: “When I see dogs looking in the mirror and feeling beautiful, I feel like I am going to cry tears of joy.”
The guides always gave the same advice: “Leave them alone and they will leave you alone.”
You can also use a colon if the quotation itself is an independent clause.
The prisoner uttered: “Leave me alone.”
This time our introduction is not an independent clause but the LEAVE-ME-ALONE is.
So if anything either side of the colon is an independent clause, then you can use a colon to introduce that quotation. 


Colon to Add Emphasis to Any Explanation

Look at the following examples:
Her success comes from her best attribute: determination.
There is one thing I really love: hard work.  
She knew what her wish would be: the ability to turn stones into gold

Colon to Introduce Bullet Points

He voted for the following films:
  • Life With Father
  • Of Mice and Men
  • Home Alone
  • The Pursuit of Happyness
Or
He voted for:
  • Life With Father
  • Of Mice and Men
  • Home Alone
  • The Pursuit of Happyness
There is a bit of leniency with bullet points, but the best thing to do is to add the word the following and then give your list of things.  
You CANNOT use a semicolon with the bullets points.
He voted for the following films;
  • Life With Father
  • Of Mice and Men
  • Home Alone
  • The Pursuit of Happyness
 It is incorrect.

Conventional Use of a Colon
 
Conventional use means the following special circumstances:

Time Designations
06:30 a.m.

After a formal salutation
Dear Sir or Madam:

To separate a title from its subtitle
“How to get your own way: Who's manipulating you?”
Here we've got a colon that's separating the title of a book from its subtitle.
You should capitalize the first word both

Colons are also common in Quran and Bible references.
Al-Mulk 67:1
Or
67:1, i.e. surah 67, ayah 1
(Quran reference)
Genesis 1:1
(Bible reference) 

Bright Tips💡

  1.  Colon gives more emphasis to lists. 
  2.  No punctuation after “such as”, “including”, etc.
  3.  Place colon only at the end of a sentence.
  4.  It’s your choice whether or not to capitalize after the colon. Just be consistent throughout your writing. 
  5. In a direct speech, you can use a colon if the first part is a complete sentence.
The teacher would say: “Do your homework.” ❌
The teacher would say the following: “Do your homework.”✅
Or
The teacher would say, “Do your homework.”