Videos
A-Level Computer Science
Pick a topic to watch.
9 video lessons
17:17
Topic 8
Databases & the Relational Model
Before databases, each program kept its own flat files — one file per program. Picture a shop. The sales program, the billing program, and the shipping program…
15:14
Topic 13
User-Defined Data Types
A plain string field will happily store nonsense. Ask for a vehicle type, and someone types Bananas — the program accepts it without a murmur. But if you…
11:17
Topic 14
Why Protocols Are Needed
Two computers want to talk, but one sends its data one way and the other expects it completely differently. The result is gibberish — like two people speaking…
15:02
Topic 15
RISC, Pipelines & Logic
Two chip designers face the same problem: make programs run fast. One says — build powerful instructions, so each one does a lot of work. The other says — keep…
14:05
Topic 16
Resources, Compilers & RPN
Open a browser, a music player, and a game. You have one processor — maybe a few cores — yet all of them seem to run at once. And together they want more…
13:19
Topic 17
How Encryption Works
Look at the padlock in your browser's address bar. You typed your bank's name, and somehow your laptop is now certain it is really talking to the bank — and…
13:11
Topic 18
What AI Is
Nobody ever wrote the rules for telling a cat from a dog. No programmer sat down and typed "if it has pointed ears and whiskers". And yet your phone does it…
15:33
Topic 19
Searching & Sorting
A phone book with a million names. If you check them one at a time, you might make a million comparisons. But you already know the trick: open it in the…
13:48
Topic 20
Programming Paradigms
Here is one job: list every student with an A grade. One programmer writes a loop — start at the first record, check the grade, add the name to a list, move…