Mood is the form of verb that shows whether the action is factual or non-factual

Types of Verbal Moods:

There are three moods in English: 
  1. Indicative Mood
  1. Imperative Mood
  1. Subjunctive Mood

Indicative Moods:

Indicative Mood expresses facts, questions and real condition.  

I do my work.
They are singing folk songs. 
What do you do in the afternoon?
If it rains, we shall play the game of chess. 

Imperative Moods:

Imperative Mood expresses order or request. All imperative sentences are in imperative mood. 

Do your work. 
Sing folk songs. 
Let us drop the matter here. 
Let them go. 

Subjunctive Moods:

Subjunctive Mood expresses wishes, possibilities, or uncertainty. We can use subjunctive mood after a very small number of verbs: wish, want, desire, suggest, insist, recommend; after some adjectives: it is important that, it is imperative that, it is essential that; and after subordinators: if, whether, lest and on condition that. 

I want he do his work. 
I wish I were a child again. 
The speaks as if he knew everything. 
If I were you, I would go there.