I recently read a book riddled with sentence fragments. Although I truly enjoyed the story and the tension between the characters, I found the writing style a little distracting. The over use of short, fragmented sentences made the writing a bit choppy. Consequently, I wasn't able to submerse myself as fully into the story as I would have liked.
Sentences. That are not complete. But punctuated. As if they are. Are called sentence fragments.
In other words, a sentence fragment is a group of words punctuated as a complete sentence but which lacks a subject, a verb, or both, and which doesn't contain a complete thought. Here's an example: Note, the last line in the following paragraph is not a fragmented sentence.
Intrepid mountain climbers scaling a tall peak. Climb higher and higher. Up the frozen slopes. When they reach the top. They can look forward to an even more treacherous descent.
When sentences are not correct or finely tuned, the quality and clarity of communication is lost.
Yes, there are going to be times when a writer needs to write in sentence fragments. People think in fragments. People speak in fragments. With some exception, a formal straight narrative usually calls for complete sentences to convey a meaning or an idea, but during interior monologue and especially in speech, sentence fragments are allowed. So "Hey you, with the stupid-looking face!" or even a simple, exclamatory, "No!" are all acceptable sentence fragments.
But woe to the writer who doesn't understand the difference between a sentence fragment used properly and one that is wandering alone, confused and misplaced, in one's work. Abused, sentence fragments can drown an otherwise coherent piece beneath a series of awkward, stilted sentences. Used to their best advantage, they can help a writer looking to vary the cadence of her piece, add emphasis where needed, or get a point across quickly.
So the sentence fragment need not be shunned, but rather learned about and embraced as a useful too. Such is the life of a sentence fragment. Simple. Short. To the point. The end.