What is AMP?
Accelerated Mobile Pages (AMP) is an open source initiative designed to ensure faster websites on mobile devices (smartphones and tablets). Google is one of the initiators of AMP and they prioritise AMP pages in their search result rankings. AMP pages are basically a stripped-down version of your website, with only the most important things included, so that the site loads in no time. For example, forms and JavaScrips cannot be on an AMP page, nor do images load until you get to them, not all at once.
You can read more about the AMP pages and see a demo if you open this link on your mobile: g.co/amp
The launch of AMP is in line with Google's stated desire to give users the results they are looking for. And one of the things we as users are looking for is speed. Pages that load too slowly are killers to access and the vast majority of us will click away if we have to wait more than a few seconds.
Do you need to make an AMP version of your site?
The AMP version of your site is up to you. To do this, Google has produced a very easy-to-follow guide, which you can find here. In WordPress there is also an AMP plugin, and there will probably be more, since the whole AMP setup is made as open source, which everyone has access to.
The question, of course, is whether it's worth the trouble?
Google itself says that it is mainly larger websites with a lot of content, images and ads that they had in mind when developing the AMP initiative. Therefore, it makes sense to invest time in creating an AMP version if your website is very content-heavy, e.g. has many articles, recipes, etc.
However, there is little doubt that AMP and speed in general play a big role for Google, so it is in any case a good idea to keep an eye on developments on that front. Another new option that could boost speed on mobile devices is PWA. For many it will be a better alternative to AMP (although PWA is still a relatively new technology and therefore used by only a few).