I am not sure if it's part of the ANSI standard, but the AmigaDOS shell supported a set of ANSI codes that provided single line stepping - not a whole text line/row, but a single raster line - allowing for pretty advanced graphics rendering by overlaying rows of text shifted by just one or two pixels vertically. It was a tad fancier than the very common ASCII art, being used in the same venues and always a "treat" to come across, though not as common due to the size and additional time needed to render.
I recommend starting with ECMA-35. The actual structure of escape sequences is explained there. Otherwise it gets lost that it's the ESC [ that is the entire escape sequence, an alternative form of CSI, and that this actually is one part of an entire mechanism of escape sequences with intermediate and final bytes. It's a control sequence that CSI then introduces.
Then find DEC and XTerm extensions https://invisible-island.net/xterm/ctlseqs/ctlseqs.html