Minimap

A minimap is two things stacked on each other. The first is the whole document drawn too small to read, so that its shape survives and its words do not: the ragged right edge of prose, the stepped indentation of a nested block, the solid slab of a table, the blank stretch where a section ends. The second is a translucent box laid over that drawing to say which slice of it you are currently looking at. Between them they answer a question a position indicator cannot: not only where am I, but what else is there.

This is the overview plus detail arrangement, where a compressed view of everything sits permanently beside a readable view of one part, and the two stay locked together. The map is read as texture rather than as content, which is why it works at scales where no character is legible. People navigate by remembering that the thing they want was near the wide block two thirds down, and the map is the only place that memory has anything to hold on to. It is also a control, not a picture. Drag the box and the document scrolls under it; click anywhere on the strip and the view jumps there.

The pattern came to most people through code editors. Sublime Text shipped it as a signature feature, VS Code made it a default, and design tools borrowed the same idea for canvases, where the map covers two dimensions instead of one. A leaner relative is the overview ruler, a narrow strip that draws no text at all and instead marks positions worth knowing about: search hits, errors, changed lines, other people’s cursors. That variant is often the better trade, since the marks are the part a reader actually navigates by.

Most interfaces do not need one. A scrollbar already reports position and proportion, and it does it in fourteen pixels rather than sixty. A minimap earns its width only when the content has visual structure worth compressing and is long enough that scrolling to look is expensive, which rules out a settings page and most article pages. It also has real costs: it renders the document twice, it stops meaning anything once a file is long enough that a line is thinner than a pixel, and it is a pointer only affordance. Keyboard and screen reader users get nothing from a drawing of the text, so the minimap must always be a shortcut to somewhere reachable another way, never the only route.