Pixel art
An image built by hand one dot at a time, where every single pixel is a deliberate decision.
Adele Goldberg and Robert Flegal of Xerox PARC coined the phrase in 1982, but the craft was already routine on home computers. With 16 or 32 colours and a resolution where a face in profile got twenty pixels, there was no room for loose sketching. The artist — the "pixeller" in scene parlance — placed each dot, anti-aliased edges by hand and leaned on dithering to fake the in-between tones the palette lacked.
On the Amiga the tool was Deluxe Paint; on the C64 you chose between hires and multicolor and lived with the trade-offs. Graphics competitions at demoparties kept the form alive, enforcing a no-scans, no-conversions rule that was as strict as it was hard to police. That indie games now pick the look voluntarily would have struck a 1988 artist as pure masochism.