Learning about Figurative Language
Many idioms are well known but they can be unique to particular cultures. They might be very confusing to other people.
You might use idioms when you write if you are trying to show dialogue between two characters as a way of making the conversation seem informal and realistic.
Examples of idioms:
'kick the bucket' means to die.
'the ball is in your court' means it is up to you to take the next step.
'beat around the bush' means avoiding the main topic.