Or online at writingsems.com

In the header of this blog, I included a sentence fragment. I wrote
"…Rosemary Camilleri teaches writing to your people, at your site. Or online at http://writingsems.com."

That last group of words is not a sentence. It's acceptable in advertising (sometimes) in order to drive home a point. But fragments are not a good habit.

You have seen other fragments:

1. Whatever the carpenter specified in the contract.

#1 above is called a subordinate clause. (Clauses are meaningful word groups that contain at least a subject and its verb.)

Subordinate clauses begin with certain conjunctions (and conjunction-like words or phrases). Here are most of them:

The List
after, before, since, until, although, how, so that, when (whenever), as, if, that, which, where (wherever), in order that, though, whether, as if, as though, once, what (whatever), while, because, provided, given, unless, why, who (whoever), whom

If you have written a clause, and it begins with one of those words, you cannot correctly end it with a period. It is only a subordinate clause:

2. Although Ali drives a gray car
is a subordinate clause. To be correct, it must be joined by an independent clause:

3. Although Ali drives a gray car, he also owns a red one.
4. Ali owns a red car, although he drives a gray car.

5. Because Ali drives a gray car, I sometimes forget that he owns a red one.
6. I sometimes forget that Ali owns a red car because he drives a gray one.

When the "because" clause shifts to the end, do you notice what happens to the comma?