A four-digit number is a numerical value that consists of four digits, ranging from 0000 to 9999. Each digit in a four-digit number has a specific place value: the thousands, hundreds, tens, and units. For example, in the number 2457, the digit 2 represents two thousand, 4 represents four hundred, 5 represents fifty, and 7 represents seven. Four-digit numbers are commonly used in various contexts, such as in ZIP codes, years, and identification numbers. They help categorize and organize information efficiently. Understanding four-digit numbers is essential for tasks like reading dates or processing numerical data in everyday life.