Semicolons with conjunctive adverbs (e.g. however, therefore, unfortunately, etc.).
How to choose between a semicolon and a period.
Semicolons - the Punctuation Mark Suffering from a Major Identity Crisis...
When to use semicolons and how to use them correctly can be very confusing. Often referred to as "soft periods," semicolons offer a continuity to sentences that periods don't.
Periods vs. Semicolons
A few sophomore students put together a nice video on semicolons and commas - it will make you laugh!