What is the difference between Case-Sensitive and Case-Insensitive

Answer 1

Case in/sensitivness is used to refer to a way how programming languages differentiate between keywords, variables, definitions, etc.
As the names imply, the main difference is in allowance of upper/lower case characters to refer to some predefined key, respecticely:

(Lets suppose we declare two variables named “Adam” and “adam”)
Case Sensitive:
variable names “Adam” and “adam” refer to two different variables because they differ in case of the first character and the language parser is SENSITIVE to these differences.

Case Insensitive:
variable names “Adam” and “adam” both refer to the same variable which can be accesed by both calls even tho they differ in the case of the first character, we can say that the language parser doesnt take into account upper/lower case changes.