Just 5 minutes ago, I was reading about the Bloom plugin in some website, and when I went to another browser tab without closing that tab,

I saw this...



Now, I have seen this before, but I was always intrigued and curious on how this brilliant and smart marketers or developers managed to do something like this. Is this a Plugin or some kinda of Code or script!

Can Anyone please explain what's this, I search on Google but not came up!!