Punctuation marks are the road signs of written English. Without proper punctuation, even great ideas become difficult or confusing to read.
1. The Comma Splice Error
Never join two complete independent thoughts with just a comma!
Incorrect: I loved the presentation, it was very informative.
Correct: I loved the presentation; it was very informative. (Use a semicolon)
Correct: I loved the presentation, and it was very informative. (Use comma + conjunction)
2. When to Use a Semicolon (;)
Use a semicolon between two closely related independent clauses where no coordinating conjunction is used.
3. When to Use a Colon (:)
Use a colon after a complete sentence to introduce a list, an explanation, or a quotation.