Markdown, but with a third axis you name yourself.
time · frames · layers · depth · space · slides · floors - same file, you choose what Z means
Open the viewer & editor · Read the docs · Browse all 270 examples →
Know Markdown? You know 3md. A version line is the magic marker, an axis names what depth means, and @plane directives slice the document along Z. Everything between directives is ordinary Markdown. Every view above is parsed by a faithful JavaScript port of the Swift ThreeMD parser, running in this page.
--- 3md: 0.1 # required version, the magic marker axis: time # anything: time, frame, layer, depth, space... title: My Week --- @plane z=0 label="Monday" # a slice along Z # Monday - [ ] Standup