Whats the meaning of case sensitive

Answer 1

Case sensitive usually is used for environments like programming languages to mean that the capitalisation of letters matters. As an example, a case-sensitive language (or whatever) recognises the variables myvariable and myVariable as different. By the other hand, a case-insensitive language treats them as the same variable!

Answer 2

then python is a case sensitive language. so it recognises both lower case and upper case letters.. am i right

Answer 3

yes you are right.
if you try this:
a=1
A=2

you'll have created teo different variables a and A