www programming

Would like remember to all SEO lovers, that spiders are leaded to index sites, basically and mainly for these reasons: content of the page, contents related title, external links that point to it, contained links and related external content, searches related clicks. All this give relevance.
Not NICE links. AND NOT HTML pages.
This should be very curious if on 2016, a web crawler go to index a page due to his extension or file name, and not due to his content and/or the above mentioned.
Meta description and Meta keywords are also important. All the rest is like a fake/palliative therapy. You can expect too much from, but you'll lead to nothing good, if the above, more important, is not as need to be.

Which is why one of the most simplest things you can do is leave a hyperlink in your post signatures and be active.

I agree with everything Alessio has said, and although phpBB doesn't need much help for meta indexing, here's an interesting SEO phpBB extension I've put together for the hell of it anyways! There is an ocean of information about SEO on the web. Keep it in simple. Relevant content, and a lot of it, no dupes. Links to that content on web. And most importantly, USE RELEVANT META DESCRIPTIONS & KEYWORDS, based on content! (keyword/tag debate, use them anyways can only be a plus, not a negative!)

Link to free download: https://forums.thetopfew.com/viewtopic.php?f=53&t=752

And this is why you post such things. Boosting my site content!