ADSL :-Asymmetric Digital Subscriber Line (ADSL), like ISDN, uses an upgraded phone line, all-digital technology, and supports simultaneous Internet browsing and phone use. ADSL is a much newer technology. ADSL is optimized for the more downloads than uploads. The line is asymmetric, because it has more capacity for data received by your computer than for data that you send.
The downstream bandwidth from the Internet to your computer can range from 384Kbps to 8Mbps. The upstream bandwidth from your computer to the Internet can range from 90Kbps to 640Kbps. Moreover, ADSL is just one of a family of DSL products