Question

define case sensitive

Answer 1

In computers, uppercase and lowercase text may be treated as distinct or equivalent. For example, the following are sometimes case-sensitive, sometimes not: Usernames File names Tags Commands Variable ... 

Answer 2

A case-sensitive program that expects you to enter all commands in uppercase will not respond correctly if you enter one or more characters in lowercase. It will treat the command RUN differently from run. Programs that do not distinguish between uppercase and lowercase are said to be case-insensitive.

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