Cellphone plan subscribers are familiar with data limits, but those limits are less understood — and more controversial — in the cable industry. A decade ago, Time Warner Cable dropped a plan to limit customers' internet use after a public outcry. Charter Communications Inc., which sells internet under the Spectrum brand, agreed in 2016 not to implement limits for at least seven years; it made that promise so it could get regulatory approval to buy Time Warner Cable and Bright House Networks.