Microsoft have announced that Flash will be disabled by default in their Edge browser in its next major update.
Flash was ubiquitous on the internet for many years. It began to gain traction for people to add flair to their websites with animations and fancy menus (and occasionally entire websites). Once Youtube started using it as their delivery method for all their videos, it was soon installed on pretty much every PC in the land.
However, it was frequently plagued by security issues (having such a large install base makes it a prime target for hackers). It also tended to be a resource hog. As browser technology has evolved to the point that video displayed without using Flash, browser creators have begun slowly pulling the plug(in) on it.
The current trend is towards disabling any Flash element on a webpage by default, and requiring the user to click on it to allow it to load on a case-by-case basis. Given that it's mostly just adverts that use these techology these days, it won't take long until the advertisers stop using it too. There's not much point creating adverts that no-one will see! It's likely that this will probably be the death knell for Flash, and it will be gone entirely within a couple of years.