What is an couplet rhyme?

A couplet is a type of poetic device. It is a stanza of only two lines that usually rhyme and share the same length. Ultimately, the two lines should form a complete thought. Shakespeare's sonnets are a good example of a couplet.

An example of a couplet comes from Shakespeare's 116 Sonnet:

"...Love alters not with his brief hours and weeks,

But bears it out even to the edge of doom.

If this be error and upon me proved,

I never write, nor no man ever loved."

In this example, the last two lines make up the couplet.