Page speed refers to how fast content on your webpage takes to load. There are many ways to measure this (for example, from first contentful paint, to speed index, to large contentful paint)—but one of the most meaningful ways to define page speed is by time to interactive.*
Time to interactive is how long it takes a page to load to the point where a user can interact with it. This might mean clicking on a CTA, choosing to play a video, or any number of actions a user can take on a given page.
Your next question is probably, “what is considered good website speed?” While the answer to that is industry specific, it’s highly recommended that, on average, your pages load in under three seconds. It’s also important to remember that page speed times can vary across different pages of the same site, as well as across mobile and desktop.