A timeline is one of the most universally useful UI patterns on the web. You'll find them in: Editorial storytelling — historical events, anniversaries, biographies Project tracking — Gantt-style timelines for tasks and deadlines Operational dashboards — flights, broadcasts, manufacturing runs Data exploration — log analysis, network events, user activity Personal apps — calendars, journals, fitness tracking But "timeline" means wildly different things depending on the context — and most articles online lump everything into one big bucket. A storytelling timeline (like Knight Lab's TimelineJS) and an operational scheduling timeline (like ScheduleJS) share zero implementation details despite having "timeline" in the name. This post compares 7 JavaScript timeline visualization libraries evaluated on the same 8 criteria , with clear notes on which type of timeline each one is actually built for. How I evaluated each library Timeline type — Storytelling, operational, data-exploration, hybrid?…