Sequence and time

Puts events on one time axis, so the order, the size of the gaps, and the moment something passes to someone else all show.

You and your housemate have had the same argument four times in three months. Afterwards each of you describes it the same way, and the description is about the other person: he gets defensive, you nag. That description has no clock in it. It says what happened but not when, and not how long the gaps between the parts were, so every retelling reaches the same conclusion and the same non-fix.

Sequence and time lays the events on a shared axis where distance means elapsed time. Once they are on that axis, three things stop being invisible. Order: what came first, and whether swapping two things would have changed the ending. Delay: the empty stretch between one event and the next, drawn as width rather than left to memory. Handoff: the moment something leaves one party and lands on another, drawn as an arrow that crosses between lanes. A list of the same events holds all the facts and none of these three.

It has five renderers. A timeline puts events on one axis. A storyboard cuts the same span into a few panels, one per phase, each drawn as a small scene rather than a label. A sequence diagram gives every party a lifeline and draws each message as an arrow between them, so handoffs and waiting become the picture. A Gantt gives every piece of work a bar whose length is its duration, stacked so overlap and idle stretches show. A lifeline follows one thing from beginning to end and marks what happened to it along the way.