A static website, also called a flat page website, is a composed of webpages that are delivered to the user exactly as they are stored.
This is in contrast to dynamic web pages that are generated in a server by a web application or a content management system
These webpages are HTML documents stored in a file system and delivered through a web server over the HTTP protocol.
These pages are ideal for content that never or rarely changes. Some key advantages and disadvanges are noted below.
Advantages of a static website:
If you are not planning to create your own content or you are only planning to edit a smaller portion of your
website (e.g.: you only need to update the menu once a month), then a static website is an excellent option.
If, in contrast, you will want to have control over your website, and perform actions like adding whole new sections or pages, a CMS based website will be a better option. This is perhaps, the most important consideration in choosing one over the other.
The second important difference is the simplicity of hosting it and the portability of the site.
Static Websites can simply be copied from one server to another with hardly any external dependency. Creating a backup is also as simple as copying those files somewhere safe.
Depending on how technically savvy you are, you may be able to do this yourself or you may need a bit of help. But in either case it only requires minimal effort.