Understanding Timelines

Have you ever looked at photos of yourself as a baby, then as a toddler, then as you are now? Without realizing it, you were reading a timeline of your life! A timeline is a visual tool that shows events arranged in the order they happened — from oldest to newest. Historians use timelines to understand how the world has changed over time.

What is a timeline?

• A timeline is a line — or series of points — that shows events arranged from the past to the present (or future).
• Events are placed in chronological order — that means in the order they actually happened, from first to last.
• Example: 1492, then 1776, then 1865, then 1969 is a chronological sequence of dates.

Parts of a timeline

• Event — something important that happened at a specific moment in history (e.g., a discovery, a war, an invention).
• Date — the year, decade, or period when that event took place, written beside its marker on the line.
• Sequence — the order of events from earliest to most recent; on a horizontal timeline, earlier events are always on the left.
• Interval — the equal spacing between time markers (e.g., every 10 years, every 100 years).

How to read a timeline

• Start at the left end — that is the oldest point in time.
• Move right — each step forward in time brings you closer to the present.
• Read the date and the event label at each marker.
• Ask: Which event came first? Which came last? How much time passed between them?