Conjunctions
A word that joins words or groups of words together.

Coordinating Conjunctions
and
but
or
nor
for
so
yet

EX:  Glasses and contact lenses help people to see for miles.
Our eyes are smaller than insects' eyes, but their vision is more complex.

Correlative Conjunctions
Pairs of words that connect words used in the same way.
Both...and
Either...or
Neither...nor
Whether...or
Not only...but also

EX:  Both dogs and cats have for legs.
       We will either go shopping today or tomorrow.