my Unity MonoDevelop doesn't recognize the "input" keyword, what to do?

so I just started out with unity 5.6.6f2 and I was scripting on windows 7 in monodevelop and when I wrote the "input" keyword in the source code and it didn't turn blue like all other keywords instead it says "No completions found". Can anybody kindly tell me what's wrong and what I can do to solve the problem?

 

Input, not input.

You are wanting to reference the name of a class, and all class names start with a capital letter.

 

Basically, you have a typo. Caps are inportant.
https://docs.unity3d.com/ScriptReference/Input.html

And you can always double check Unity's examples in their docs.

 

Also make sure you have "using UnityEngine;" near the top of your file.