This file configures LnBlog’s file writing and allows you to set the document root for your web server (it will try to auto-detect this).  It creates the userdata/fsconfig.php file.

There are two options for file writing.

Native FSUses PHP’s native filesystem functions.
FTP FSWrite files through an FTP connection (usually to localhost).

Note that there is a trade-off here.  Native FS has no special requirements or configuration in the software, but, if your host is pporly configured, may require manually changing file permissions due to the fact that it runs as a system account.  FTP FS, on the other hand, requires the user to enter an FTP username, password, host name, and the root of that user’s FTP access (assuming the user cannot access the entire filesystem).  However, with FTP FS, LnBlog can create files as the configured user account, rather than a system account like “apache” or “IUSR_whatever”.  FTP FS is recommended when you are forced to run under PHP’s “safe mode”.  However, since this is now deprecated, it is probably best to use Native FS.