> For the complete documentation index, see [llms.txt](https://emotiv.gitbook.io/emotivpro-v3/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://emotiv.gitbook.io/emotivpro-v3/event-markers/about.md).
# About event markers
You can add event markers to specific events or areas of interest while recording your EEG data. Adding event markers means you can easily find events during playback or analysis.
EmotivPRO allows you to insert markers into the data stream manually via your computer’s keyboard, or via to a serial port (or virtual serial port), USB port or Extender to allow other applications to present stimuli and mark the events automatically. Any marker entered will display in the data stream and on the recording timeline during playback and will be indicated alongside other data streams in the application’s exported CSV files.
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