Question

What is the purpose of juxtaposition in English?

Answer 1

Juxtaposition is the placing of two things (words, situations, images etc) close to, or opposite, each other for the purpose of comparison, to gain an effect of some kind.

Explanation:

Examples:
Picture of John before a diet next to picture of him after a diet.
It was the best of times; it was the worst of times... (Dickens)