You can use it to get detailed data about exactly where Welsh speakers live and see how patterns have changed over time, as well as find out more about the lives of these speakers.
Gallwch ei ddefnyddio i gael data manwl am ble yn union mae siaradwyr Cymraeg yn byw a gweld sut mae patrymau wedi newid dros amser, yn ogystal â darganfod rhagor am fywydau’r siaradwyr hyn.