Interactive explainer
How GPUs work
A CPU has a few very fast cores that each do one thing at a time. A GPU has thousands of slow ones doing the same thing to different data, all at once. Paint the same picture with both and watch.
CPU 8 fast cores · one pixel each per step
pixels done0
GPU thousands of cores · a whole row per step
pixels done0
Press Paint both.
Why it works
Where it does not
When each step needs the answer of the one before (a chain of if-this-then-that), thousands of cores just wait in line. That is still a CPU's job. Graphics, matrix maths and neural networks are the opposite: millions of small, independent sums.
Numbers are illustrative. Made with an agent and published with pages.flisk.si.