x is a variable often used in mathematics and programming to represent an unknown value or a placeholder. It can stand for numbers, objects, or any other type of data, depending on the context. In equations, x is commonly used to solve for a specific value, making it a fundamental concept in algebra. In programming, x can be used as a variable name to store information. For example, in languages like Python or Java, developers assign values to x to manipulate data and perform calculations. Understanding how to use x effectively is essential for problem-solving in both math and coding.