Do I need a domain name to make a website?

While you can run a website without a domain name, it'll be harder for others to find and track using an IP address alone. For webservices only for Local Area Networks or running on one's machine, just the host name (such as "kitchen1" or "localhost") can be used, which'll point either to their local/private IPA or a loopback address. Using just an IPA globally/publicly however may impact search-engine listings. Some website software and such may not be compatible with IPA hostnames/URL's either. Browser bookmarks would have to be updated if a site's IPA has to change too, which is often the case when changing servers, let alone hosting providers. So if you want a publicly accessible website, you usually need a domain name.