You have to visit websites individually in order to check whether they are updated.
The more websites you have that you read regularly, the more time you have to spend just to check whether they are updated, often in vain.
Content Syndication
Unfortunately, there are three families of competing standards as applications of XML for syndicating websites:
RSS (Really Simple Syndication)
RSS (RDF Site Summary)
Atom
You syndicate your website with an RSS/Atom feed that includes hyperlinks to site-internal contents and metadata about them.
People can automatically aggregate RSS/Atom feeds for your website and those of others, receive lists of updated metadata in a single interface and decide whether to actually visit there by following the links.
RSS News & Blogs [integrated; the name "RSS News & Blogs" should be changed to something like "RSS & Atom Feeds" or simply "Feeds" to better reflect the nature and reality of content syndication]