> For the complete documentation index, see [llms.txt](https://docs.widgelix.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.widgelix.com/get-started/devices/history.md).
# History
The **History** tab allows you to visualize data from selected fields of your device on an area chart over a period of time. By default, all data fields are enabled and shown on the chart.
You can remove a data field from the chart and add it back to the chart by clicking on the corresponding row of the table. This feature is useful when you want to compare trends in different data fields.
For example, the following chart compares the relationship between temperature and humidity over time.
For data filtering, choose the desired timeframe using one of the following options:
* Click on the **text box** and select a predefined timeframe from the list. If the desired timeframe is not available, you can manually type a timeframe, such as '3 days', '7 weeks', etc. Note that '3 days' refers to the last three days, including today, for example. Here is a list of predefined timeframe presets: `1 hour`, `1 day`, `1 week`, `1 month`, and `1 year`.
* Define a custom date range by selecting the **start date** and **end date**, including the start time and end time too from the date pickers.
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