I see that search engines are prominently capable of finding pages chronologically for forum websites and the like, offering the option to show the results for the last 24 hours, last week, last month, last year, etc.
I understand that these sites need to be continuously crawled to provide those updates, but I have technical doubts about what structure, tags or whatever I need to do to achieve it for my website.
I see that at the client side (which is also the side search engines are at) content appears basically as static data, already processed by the server, so the question is:
If I have a website for which I update and add content constantly to the index page to make it easily visible, and for which I even add links, times and dates as text for the new pages, why don't these updates show at all in search engines?
Do I need to add XML/RSS feeds, or what else?
How do forums and sites with heavy updates with a chronological mark achieve the capability to allow search engines to list results separated by hours, days, etc.?
What specific set of tags and overall structure do I need to add for this feature?
I also see that search engines, mainly Googlebot, usually take a minimum of 3 days to crawl those new pages, but still, they aren't organized persistently (or at all) in a chronological way in search results.
I am not using any forum, blog or other kind of web publishing software, just raw HTML and PHP written by hand, and the minimum I mentioned above, of pointing to new documents from the index page of the website along with a description.
Do I need to add XML/RSS feeds, or what else?
Yes. Atom or one of the RSS formats (or several formats at the same time, so you could offer Atom and RSS).
Search engines will know about new blog posts, microblog post, forum threads, forum thread answers etc., because they subscribe to the feed. So sometimes you'll notice that a page is indexed by a search engines only minutes after it was published. But for smaller sites, search engines probably don't check for updates every few minutes, instead it might take even days until a new page is indexed.
A sitemap might help, too.