Loom

Threading, across the top: every warp end passes through the eye of a heddle on one of the four shafts. A square marks which.

Tie-up, top right: each treadle is tied to the shafts it lifts. Press a treadle and every end threaded on those shafts rises, opening the shed for the shuttle.

Treadling, down the right: the treadle for each pick, in order. Beside it, the colour of each pick; above the threading, the colour of each end.

Drawdown, the big grid: the cloth worked out on paper. A square is filled where the warp lies on top. Weavers used to fill these in by hand, cell by cell; it is the threading, the tie-up, and the treadling multiplied together.