Like human languages, programming languages have rules and components:

• Lexis: The set of all valid words or symbols in a language. In Python, this includes keywords (like if, for, def), operators (+, =, >), and identifiers (variable names).

• Syntax: The rules that govern how words and symbols can be combined to form valid statements or expressions. For example, in Python, an if statement must end with a colon (:), and the code block below it must be indented. if x > 5: print("Greater") (Correct syntax)

• Semantics: The meaning of syntactically correct statements. A program can be syntactically correct but semantically wrong if it doesn't do what the programmer intended. For example, using + to add two numbers has a clear semantic meaning. If you try to add a number and a string without proper conversion, it might be a syntax error or a semantic error (a TypeError in Python) depending on the language.