This deep dive covers Deep Dive: The Three Basic Logic Gates within Logic Gates for GCSE Computer Science. Revise Logic Gates in 3.4 Computer Systems for GCSE Computer Science with 16 exam-style questions and 20 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 3 of 9 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
Deep Dive: The Three Basic Logic Gates
AND gates are like security doors that need BOTH a keycard AND a fingerprint. Only when ALL inputs are 1 (true) does the output become 1. It's the strictest gate - everything must be true.
OR gates are like motion sensors that trigger if EITHER the door sensor OR the window sensor detects movement. If ANY input is 1 (true), the output is 1. At least one condition must be met.
NOT gates are inverters - they flip the signal. If the input is 0, output is 1. If input is 1, output is 0. Think of it as a "do the opposite" gate.
Why this matters: Every single computation in your computer - from calculating 2+2 to rendering 3D graphics - ultimately comes down to billions of these simple gates making binary decisions at lightning speed.
Practice questions for Logic Gates
An AND gate has inputs A=1 and B=0. What is the output?
Complete the truth table for an OR gate with two inputs A and B. | A | B | Output | |---|---|--------| | 0 | 0 | | | 0 | 1 | | | 1 | 0 | | | 1 | 1 | |