An interjection is a word or a phrase that expresses an emotion or exclamation. An interjection is set apart from other words in a sentence. Interjections have an exclamation point or a comma (when the feeling is not so strong).
Interjections are usually used in speech. You should use them sparingly.
Interjections can express different emotions.
Example: Wow! This is super! [Express joy]
Example: Oh, no! Look out below. [Surprise]
Ouch! That really hurts. [pain]
Example: Great, I’m out of here.
Here is a video for this topic: Interjection