system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why are webpages white by default rather than black?

I know obviously its easier to read text on, but why wouldn't the computer interpret a lack of input as black, seeing as #000000 and rgb(0, 0, 0) are both black?
gpt
The background of a web page isn't determined directly by some absence of data.  The earliest widespread browser, Mosaic, used grey as the default background.  But it didn't take long for white to be chosen as the default by other browsers, matching the defaults on both Windows and Macs.  

In other words, the people who implemented the early browsers made a conscious decision that if they weren't told by the web page to use a specific background color, they'd use white.