What does syntax refer to in programming languages?

In programming languages, syntax refers specifically to the set of rules that define how code must be written in order for it to be correctly understood by the compiler or interpreter. This includes the proper arrangement of symbols, keywords, and structure in writing statements and expressions.

When a programmer writes code, adhering to the syntax rules ensures that the code can be parsed and executed without errors. For example, if a programming language requires that a function be declared with a specific format (such as including parentheses or curly braces), failing to follow those rules will result in syntax errors.

Understanding syntax is fundamental for any programmer, as it serves as the foundation upon which various logical structures and functions are built. Grasping these rules allows for the creation of effective and efficient code, which is essential in any programming task.

In contrast, the other options refer to different aspects of programming. Speed of execution relates to runtime performance, the overall structure involves the logical organization of the program but not its precise code formulation, and libraries are collections of pre-written code used to facilitate specific tasks but do not define how code is written.