Conjunction

A conjunction is a word that connects other words or groups of words. In the sentence Bob and Dan are friends the conjunction and connect two nouns and in the sentence He will drive or fly the conjunction or connects two verbs. In the sentence, the conjunction connects two groups of words.

Coordinating conjunctions are conjunctions which connect two equal parts of a sentence. The most common ones are and, or, but, and so which are used in the following ways:

And is used to join or add words together in the sentence they ate and drank. 

Or is used to show choice or possibilities as in the sentence He will be here on Monday or Tuesday.
But is used to show opposite or conflicting ideas as in the sentence She is small but strong.
So is used to show result as in the sentence I was tired so I went to sleep.

Subordinating conjunctions connect two parts of a sentence that are not equal and will be discussed more in another class.

Correlative conjunctions are pairs of conjunctions that work together.