136. OCR A Level (H046-H446) SLR23 – 2.2 Functions & procedures

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About this video

OCR Specification Reference
AS Level 2.2.1c
A Level 2.2.1d

This video explores the important programming techniques of modularity, in particular the differences between procedures and functions. It includes a discussion of parameters and the difference between passing them by value and by reference.

Key questions:

- Why is it a good idea to develop code in a modular way?
- What is the difference between a function and a procedure?
- What is the difference between parameter passing by value and by reference?

00:00 Functions & procedures
00:10 Intro
00:15 A note about these videos
01:00 What is modularity?
01:31 Procedures and functions
04:40 Parameters
07:51 Passing parameters by value and by reference
08:16 Passing parameters by value
09:45 Passing parameters by reference
10:55 A note from the exam board
11:38 Key questions
11:58 Going beyond the specification
12:11 The truth
13:35 Outro

Last updated: 24.07.26

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• SLR 23 – Programming techniques