A timeline arranges events in chronological order along a horizontal axis. Each entry shows a date or period and the events associated with it. Related events can be grouped under a shared label by listing them on separate lines under the same date.

Timelines are well suited to history pages, project milestone summaries, product roadmaps, and any narrative that unfolds over time.

timeline
    title Writing in the Ancient World
    3400 BC : Cuneiform script developed in Mesopotamia
    3100 BC : Egyptian hieroglyphics emerge
    1200 BC : Phoenician alphabet created
    700 BC  : Greek alphabet adapted from Phoenician
    AD 105  : Paper invented in China

timeline
    title Writing in the Modern Age
    1440 : Gutenberg's printing press
         : Bible becomes first mass-printed book
    1868 : First practical typewriter patented
    1971 : First email sent
    1991 : World Wide Web launched
    2004 : Blogging goes mainstream
         : RSS readers become popular

Multiple events on the same date are listed on consecutive lines — the date label is written once and the remaining lines under it are associated automatically. You can place several timeline diagrams on the same page to split a long history into readable sections.

```mermaid
timeline
    title Writing in the Ancient World
    3400 BC : Cuneiform script developed in Mesopotamia
    3100 BC : Egyptian hieroglyphics emerge
    1200 BC : Phoenician alphabet created
    700 BC  : Greek alphabet adapted from Phoenician
    AD 105  : Paper invented in China
```

```mermaid
timeline
    title Writing in the Modern Age
    1440 : Gutenberg's printing press
         : Bible becomes first mass-printed book
    1868 : First practical typewriter patented
    1971 : First email sent
    1991 : World Wide Web launched
    2004 : Blogging goes mainstream
         : RSS readers become popular
```

For more timeline syntax see the timeline documentation at mermaid.js.org