What is ADSL?

     Asynchronous Digital Subscriber Line - a broadband access
technology whose main advantage is that it works over plain copper
wires (requires no special infrastructure) 
     
     ADSL works by utilizing the fact that copper wires can pass a
very wide range of frequencies, but human speech only uses a small
frequency range. The rest is available for data. 
    
    ADSL only works at a limited range, and won't work in some cases
due to specific phone company infrastructure. 
    
    ADSL requires special equipment at the end user's (an ADSL modem
or router) and at the switching office (a DSLAM). 
    
    ADSL is operating system agnostic, but requires software support.