> ## Documentation Index
> Fetch the complete documentation index at: https://docs.appsignal.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Custom markers

Markers are little icons used in graphs on AppSignal.com to indicate a change.
This can be a code deploy using a ["Deploy marker"](/application/markers/deploy-markers) or a
special event with a "Custom marker".

Custom markers can be used for anything from scaling operations, to sudden
spikes in traffic and infrastructure issues such as when a database was acting
up.

See also our announcement posts about Custom markers:

* [Introducing custom markers](https://blog.appsignal.com/2016/10/28/custom-markers.html)
* [Add custom markers from any graph](https://blog.appsignal.com/2016/11/28/custom-markers-from-any-graph.html)

## Creating a custom marker

A custom marker can be created in two ways. Through the UI on AppSignal.com on
the graphs or with a request to our API.

### Using the Graph UI

When on AppSignal.com open a page with a graph on it, any graph. Hover over a
space in a graph and you will be presented with a "Add marker" button. In the
"Add marker" lightbox, select an icon, set a message and create your marker. To
edit or delete a marker, click on the icon and you will be brought back to the
editor.

### Using the AppSignal API

There are two APIs to report custom markers to AppSignal.
These two APIs use different authentication methods.
Choose the one that's most convenient, there is no other difference.

* [Markers API endpoint documentation](/api/markers): authenticate using Personal Access Token. This authentication method has read and write access to all data.
* [Public endpoint markers API endpoint documentation](/api/public-endpoint/custom-markers): authenticate using a Push API key + app name and environment, or using a Front-end API key. This authentication method is write only.