> For the complete documentation index, see [llms.txt](https://docs.jabref.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.jabref.org/setup/externalfiletypes.md).
# Manage external file types
{% hint style="warning" %}
In general, there is no need to change the settings of external file types. So, this setting is for advanced users.
{% endhint %}
For each file link, a file type must be chosen, to determine what icon should be used and what application should be called to open the file. The list of file types can be viewed and edited by choosing **Options → Preferences**, tab **External file types**.
A file type is specified by a graphical icon, a name, a file extension and an application to view the files. On Windows, the name of the application can be omitted in order to use Window's default viewer instead.
Manage external file types
---
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```
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