That is a badly written article. And the ones for linear map and continuity linked there, which would be important to the topic, too. The good mathematical arti

That is a badly written article. And the ones for linear map and continuity linked there, which would be important to the topic, too. The good mathematical articles start with a definition after the intro. So much for teaching year olds. This is not rocket science, but mathematicians (almost inherent) inability to have language skills makes it seem so, notably.