The survey of Internet providers in the Feb. 2 Sunday Business section listed incorrect information about the e-mail services of two firms. Adelphia Power Link users can access their e-mail only via standard POP (Post Office Protocol) software; AT&T WorldNet users can use either POP mail software or a Web-mail interface, but not IMAP (Internet Message Access Protocol). (Published 2/17/03)

Who: The provider's name, Web page, e-mail address (some don't accept customer queries via e-mail), phone number and location.

Price plans: All costs in this chart are monthly unless noted otherwise. Dial-up prices are month-to-month, no-contract rates, while DSL and satellite providers may require one-year deals. Cable-modem rates exclude modem rental (it's cheaper to buy anyway) and assume you get cable TV service from the same company (if not, you'll usually pay about $10 extra per month). We exclude plans over $80 and all setup and hardware costs ($100 or so for DSL or cable, $500 and up for satellite).

Speeds listed with broadband plans ("608 kbps/128 kbps") refer to download and upload speeds under optimum conditions.

Coverage: Our estimates of where an ISP will offer local-call dial-up service, based on its list of access numbers: "Washington and adjacent counties" means the District; Arlington, Fairfax, Montgomery and Prince George's counties; and the cities of Alexandria, Falls Church and Fairfax. "Greater Washington area" means that area plus Anne Arundel, Calvert, Charles, Frederick, Howard, St. Mary's, Fauquier, Loudoun, Prince William and Stafford counties and the cities within. Check with the phone company to be sure.

With cable providers, we list the jurisdictions where they offer TV, but if your cable operator's network hasn't been upgraded for high-speed Internet service, you might not be able to get the advertised access. With DSL, take these estimates as broad guidelines; you'll need to plug in your home address and phone number at a provider's Web site to get a more definitive answer.

E-mail accounts: The number of e-mail addresses you get with a subscription and what additional accounts cost per month.

E-mail access: "POP," or "Post Office Protocol," means you can use pretty much any mail program. "IMAP," or "Internet Message Access Protocol," works better if you want to check your mail from two computers. Web-mail access lets you get to your e-mail when you're away from your computer, usually without annoying pop-up ads. "Proprietary" means you can use only the software provided by your ISP.

Spam filter: Three countermeasures kept coming up when we asked providers about junk-mail filtering, so we list them by name. "Blacklists" track sites known to assist spammers and refuse Internet traffic from them (at the cost of blocking some innocent e-mail); the Brightmail service kills the most common spam but also lets a lot slip through; SpamAssassin catches much more junk but also nukes some legitimate messages.

Virus scanning: Some providers scan for viruses in attached files for you, which can reduce -- but not eliminate -- the odds of your PC being infected.

Parental controls: We note whether the ISP includes the option of restricting kids' access to objectionable content. These systems vary in effectiveness and never work perfectly.

Web server space: How many megabytes of disk space a provider offers on its Web server for a personal Web site.

Software: If the ISP offers its own set of Internet programs, we list the operating systems it supports. "None" means you have to set things up yourself. "Required" means you must use this software to get online. "Firewall available" means this software includes a utility to stop online intrusions to your computer; if you have broadband access and your provider doesn't include this feature, you need to set up a firewall yourself.

Tech support: The hours when you might get a human to answer at the help desk. (Most providers also offer Web and e-mail support.)

Total users: The number of people doing business with this ISP can tell you both how popular it is and your chances of getting the user ID of your choice. (The largest ISPs, unfortunately, are also more vulnerable to spammers, since they constitute much bigger targets.)

Years of experience: That should be self-explanatory.

Quote: We left the last 40 words for each company to say something in its own behalf.

-- Rob Pegoraro