Go to to try out all the courses Brilliant has to offer and expand your knowledge today! Use this link to get a 20% discount on their annual membership. Have you ever wondered how CPUs work? Well, in this video, we take a 3D animated tour of a Central Processing Unit and see exactly how it works. Central Processing Units, or CPUs, are incredibly complicated, and they practically run the modern world. CPUs can be found in every desktop computer, laptop, video game console, smartphone, and any other device you use on a daily basis. CPUs are built from tens of billions of transistors assembled into billions of logic gates, and essentially they're amazingly powerful calculators. But in reality, they're more like instruction-crunching and data-moving machines. All CPUs share a common DNA, which is the Fetch-Decode-Execute cycle. This cycle is both very powerful and a critical limitation of every CPU. So dive right in and we'll show you how CPUs work. Table of Contents for How CPUs Work 00:00 - The CPU Inside Your Computer 01:45 - The Technological DNA of CPUs 03:28 - Teardown of a Laptop 04:39 - A CPU Die 05:59 - Analogy of a CPU 07:10 - Explaining the CPU Analogy 09:47 - How do CPUs Complete Instructions? 12:34 - The Program Counter 13:33 - Loops and Branches 16:01 - All Possible Instructions 17:07 - Fetch Decode Execute 21:14 - CPU Clock and Fetch Decode Execute 22:53 - Uncovering the Technological DNA: Fetch Decode Execute 23:47 - ASICs and FPGAs 24:35 - Memory and Writeback 25:36 - Sponsored Section 28:02 - RISC vs CISC 30:09 - About Branch Education 31:09 - Extrapolating to the M1 33:36 - The Diagram of a Performance Core 34:09 - CPU vs SoC 34:58 - GPU Architecture 35:55 - Thank You to Our Supporters We're working on more ambitious subjects like How AI Works Any contribution would greatly help make these videos. Branch Education Website: Branch Education Facebook: Animation Director: Mike Radjabov Primary Animators: Muazzam Azizova, Max Botirov Secondary Animators: Parvesh Khatri, Sherdil Davronov Research, Script and Editing: Teddy Tablante Twitter: @teddytablante Modeling: Prakash Kakadiya Image and Thumbnail Editing: Randy Catequista, BJ Torrejos, Adam Silven Voice Over: Phil Lee Sound Design by Drilu: Sound Design and Mix: Luis Huesca Erratum: At 5 min 34sec in, we show a NAND logic gate, when it should be an AND logic gate- we've reviewed this video dozens of times, along with having many other expert reviewers, and somehow this glaring detail got through. Funny enough, we reviewed all the binary and many other elements in close detail, but because this was such a big thing, it's probably why it wasn't reviewed as thoroughly. 4004 (dot) com. "Intel 4004 - 50th Anniversary Project Apple Newsroom. "Apple Unleashes M1" Nov10, 2020 ARM Information Center. "ARMv8 Architecture Reference Manual" Compiler-explorer (dot) com. "Compiler Explorer" Ken Shirriff's blog. "The 6502 microprocecssor chip" Visual6502 (dot) org. "Visual Transistor-levl Simulation of the 6502 CPU" Wikipedia contributors. "Control Unit", "CPU", "Instruction Register", "Integrated Circuit", "Memory Address Register", "Program Counter". Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, Visited November 11th 2025 WikiChip. "Cortex A77 Microarchitecture" #CPU #CompSci #HowItWorks