In which context do variables exist and are defined?

Variables exist and are defined within a specific context known as "scope." The scope determines where a variable can be accessed or used within a program. When a variable is created, its scope defines its visibility and lifetime.

For example, a variable defined within a function can only be accessed within that function's scope. It is not visible outside of it, which helps to prevent conflicts with other variables that may have the same name in a different part of the program.

Understanding scope is crucial for managing variable accessibility and ensuring that they retain their intended functionality without unintended interference from other parts of the code. This is particularly important in larger applications where multiple developers may be working on different modules at the same time.

While classes, functions, and modules each relate to how code is organized and managed, the concept of scope specifically focuses on the environment in which variables are created and can be accessed. This makes "scope" the most precise term in the context of defining where variables exist.