advertising. they are selling someone else, an advertiser access to the fact you go to their website. that s generally how it happens. some websites like netflix, for instance, sell subscriptions. you won t find advertising there. they re paying for the service. internet service providers sell access to those websites via broadband. they provide the internet superhighway. that s the road on which the internet travels. watching movies online, for instance, puts a bigger strain on networks than reading e-mails does. and now some internet service providers want to ration out the internet access and split it into tiers. okay. here s the problem. some interpret service providers control internet access also offer, let s say, video services of their own. let s use comcast as an example. imagine if comcast was able to limit netflix s use of the big internet pipe. it could block or slow down netflix so users instead would watch comcast videos online.