ludwa6
A bit of context in case it helps you and others that follow.
I assume you now understand single file wikis, to be accessible, they need either local file access or put it on a server you can access. You can place the file on any internet hosted folder. I use a cpanel hosting service to host single file wikis, with the tw-receiver I can also save changes to the single file. My PHP server is a static file server and external files on the same server can be accessed as external files, if you move your single file wiki you will need to move these external files with it, and if their location changes (eg folder or URL) you will have to change the links (use relative rather than absolute addresses to avoid this). You can also host wiki on tiddly-spot but not the additional files.
If using Node (install yourself) or Via TiddlyServer or Bob (including the quick install bob.exe) you can then access either single file wikis or node (folder wikis which has each tiddler as a separate file) via a url with a local or internet hosted ip address. This is great for sharing on a local LAN, or you desktop and mobile on the same network. Bob.exe handles multiple devices/tabs/people accessing the same tiddlywiki at the one time with save access. It is less common for people to have Node On the internet, if you do security demands you use a proxy server.
However with node servers, either on the LAN or the internet the
Integrated Static File Server, allows you to host external files through the node server that your single file (or node/folder wiki) can access, basically it also provides the service my PHP/cpanel host was allowing you to do and put additional files separate from your wiki "online", serving files. Another feature of node hosted wikis, is every tiddler can be made available as a static html copy of the tiddler (they are just there with the correct url) so people can load and see a single tiddler, without needing to load the whole wiki.
With single file wikis, I recommend you set up a splash screen (in tiddlywiki) so people are advised the wiki is loading so they don't see a white screen for too long, they wait to see the wiki fully loaded, rather than abandon the tab. Once loaded however the performance can be great because there is nothing else to load, until you link to an external file, and it has to be loaded.
I hope this adds a little context.
Regards
Tony