Tabs vs. Spaces
Noun · Holy War · Hacker Culture
Definitions
The oldest and most pointless debate in programming: whether to use tab characters or space characters for indentation. Silicon Valley dedicated an entire scene to it. Gofmt settled it for Go (tabs). Python settled it (spaces). Everyone else is still fighting.
In plain English: A never-ending argument among programmers about which key to use for indentation — trivial but passionately debated.