yes, this is a semicolon

A semicolon sits half way between a period/full stop and a comma. It has little or nothing to do with a colon, however.

It is used instead of a period/full stop when we want to avoid too strong a break between phrases and instead of a comma when we need a stronger break.

Breaking Up Lists

If you have a list of items, normally they are separated using a comma:

The participants will be: Eric, Terry, Neil, John, Graham, and Michael.

When punctuating a series of phrases which include a comma, you should use semicolons instead of commas to separate the phrases from one another.

Henry’s mother believes three things: that every situation, no matter how grim, will be happily resolved; that no one knows more about human nature than she; and that Henry, who is thirty-five years old, will never be able to do his own laundry.

According to our records your son missed school on Monday, May 2nd; Thursday, May 5th; and Friday, May 6th.

Joining Sentences

Semicolons can be used to join two sentences (or independent clauses) which are closely related.

I saw a man on a plane. He looked the kind of man who would put fire out with flame.

I saw a man on a plane; he looked the kind of man who would put fire out with flame.

You can use a semicolon before conjunctions like therefore, however when joining two sentences‏‎. In this case the connector must be followed by a comma.

I’m 100% positive I didn’t make any mistakes in my report; however, I’m willing to proofread it once more.

Susanna arrived about twenty minutes before Julia; therefore, she is the winner.

All these examples show a close relationship between the two joined sentences. You don’t want to use a semicolon if there isn’t a close relationship:

* I love beans; Queen Victoria was 1.52m tall.

* the asterisk denotes bad grammar

Do not place a semicolon before a conjunction‏‎ (but, as, etc) which links two sentences:

* {independent clause} + semicolon + {conjunction} + {independent clause}

* I have been waiting a long time for my divorce to come through; but now I wish I never asked for it.

I have been waiting a long time for my divorce to come through, but now I wish I never asked for it.

But if the two sentences are very long and already contain a number of commas you can use a semicolon:

I have been waiting a long time for my divorce, my terrible, long, divorce to come through; but now I wish I never asked for it.

Joining Dependent & Independent Clauses

Do not link a dependent clause to an independent clause by way of a semicolon.

* {dependent clause} + semicolon + {independent clause}

* Although achieving good results with this method is possible; research shows it is unlikely.

Instead use a comma:

{dependent clause} + comma + {independent clause}

Although achieving good results with this method is possible, research shows it is unlikely.

Other Uses

Of course there are other uses for a semicolon in today’s world…