Arizona State University (ASU) CSE240 Introduction to Programming Languages Midterm Practice Exam

Global variables are commonly used to track the state across multiple functions because they maintain their values throughout the life of a program, accessible from any point in the code after they have been defined. This characteristic allows different functions to share and update a common piece of data without having to pass that variable explicitly as an argument. For example, if multiple functions need to reference or modify a counter or a status flag, using a global variable facilitates this process, ensuring that all changes in one function are reflected in others that access that variable.

Using global variables simplifies the management of state information, especially in programs that consist of multiple functions that need to coordinate their actions based on shared data. This can lead to more straightforward code and reduce the number of parameters that need to be passed around, thereby improving maintainability and readability in certain scenarios. However, it's also important to note that excessive use of global variables can lead to code that is harder to understand and can introduce issues related to unexpected changes and increases in complexity in larger software systems.