Depending on your expected usage, you can connect to the Internet via a dial-up line or via a dedicated data line. If only one person will typically browse the Internet at a time, you should be fine with dial-up service. This means that you use a modem and a regular phone line to connect to the provider. A regular 28,800 bits per second (bps) modem is acceptable for most browsing; however, users who regularly visit graphic-intensive sites may want to consider using an ISDN connection to the ISP. ISDN offers connection speeds up to 128,000 bps, but requires an ISDN "modem" and ISDN service from your local telephone company.
When examining ISPs, make sure they offer a dial-up number in your local calling area. This will reduce phone charges for the connection. You should also inquire about the number of modems the ISP has to handle incoming calls. A good rule of thumb is that there should be one modem for every ten customers.
Businesses that will have several people simultaneously using the Internet will want to consider a dedicated line. Dedicated lines directly connect your office to the Internet service provider. You pay a relatively high monthly charge, but do not pay for each minute of connection time.
The smallest dedicated lines are 56K lines, which can handle 2 or 3 simultaneous users. However, most users will want to purchase a fractional T1 line, which can be increased to handle higher loads in 64,000 bps increments. A full T1 can handle dozens of simultaneous users, and even larger T3 connections are available for the largest firms.