All languages have a set of rules that define how the words and sentences are formed. Similarly, computer languages follow a set of rules that define how declarations, functions, commands, and other statements are arranged. This set of rules is known as the syntax of the language. A program should have the correct syntax for it to run correctly. Even the lack of a parenthesis or a semicolon can result in a syntax error. When a program runs into thousands of lines, it becomes next to impossible to discover syntax errors manually, so a debugger is used to identify errors.