A variable is a named memory location that can store a number or any other type of data that changes over the duration of the program's run. A variable can be assigned a value, modified, or used in calculations or operations. A variable is different from a constant, which is a fixed value that does not change. A variable is also different from a loop, which is a control structure that repeats a block of code until a condition is met. A variable is also different from a function, which is a named block of code that performs a specific task and can be reused12. Reference := CompTIA IT Fundamentals (ITF+) Study Guide, 2nd Edition, Chapter 4: Software Development3; What is Variable? - Definition from Techopedia