Net Neutrality is the basic principle that the internet should be free and open to everybody. To ensure this, we have rules that prohibit internet service providers (ISPs) like AT&T, Comcast and Verizon from speeding up, slowing down or blocking specific content, applications or websites. This is why your uncle's gardening blog and Facebook load at roughly the same rate on your computer or phone.
Money? Power? Fame?...Wait, no, it's just money. Money and a very powerful lobby.
Basically, ISPs could potentially charge fees to the content companies that can afford to pay for preferential treatment-your CNNs, your Facebooks, your Ubers. In the process, they'd be able to relegate everyone else - your mom's gardening blog, your brother's vaping insta page, your friend's kinda lame, but kinda genius startup - to a slower tier of service. From there they could pressure sites into paying millions to escape the "slow lane."
And this could mean more fees for you. Not only might internet cost more on the consumer end, but every site and business would likely wind up having to pay extra money to make sure their site isn't slowed down dramatically. This would be especially damaging to startups and independent voices who can't afford to compete monetarily with the Facebooks of the world.