Module 1: How Python runs your code

What a programming language is made of, how the interpreter runs your source code, and the structural rules every Python program follows.

Exam	PCEP-30-03
Section	1. Computer Programming and Python Fundamentals (17% of the exam)
Objectives	1.1.1 and 1.2.1
Exam questions	About 2, one per objective

By the end of this module you can do everything below. The objectives and their wording come from the official PCEP-30-03 syllabus.

1.1.1 Explain the fundamental concepts of programming language structure and code execution

• Define lexis, syntax, and semantics, and explain their roles in a programming language.
• Distinguish between lexical, syntactic, and semantic errors in program code.
• Define interpretation and compilation, and explain the roles of an interpreter and a compiler.
• Compare interpreted and compiled execution models, including how source code is processed and executed.
• Explain how Python source code is processed and executed, from source code to program execution.

1.2.1 Apply the fundamental structural rules of Python programs

• Recognize Python keywords and explain why they cannot be used as identifiers.
• Distinguish between expressions, statements, and keywords.
• Use indentation to define blocks of code.
• Recognize errors caused by incorrect or inconsistent indentation.
• Use comments to document code and temporarily disable selected lines of code.