companies sold busi- ness telephone systems only. Some sold local outside lines and telephone calls. Others became long distance companies or spe- cialized in data communications. Now things are beginning to change again, and a new regula- tory climate resulting from the Telecommunications Act of 1996 is permitting companies to expand into areas of the business from which they had formerly been prohibited. Companies have been merging or acquiring other companies with services that com- pete with or complement their own. It is no longer possible to identify a company as purely a local telephone company or a long distance company. Instead, we classify companies by the types of equipment and services The Telecom Handbook 273 UNDERSTANDING THE INDUSTRY they sell and support. Keep in mind that many companies now fall into more than one of these categories. Considering the pace of mergers, acquisitions, spin-offs and failures, nothing becomes out-of-date faster than telecommuni- cations company names. Telecommunications Network Services (Outside Lines And Calls) Local telephone lines come into your business, most typi- cally on cables running in from the street to your office. They connect either your telephone system or individual telephones, faxes or modems to the outside world. They include dial tone lines also known as POTS lines (POTS = plain old telephone service) or may be called auxiliary lines, combination trunks, direct inward dial trunks, T-1s, and PRIs. These lines are most typically delivered to your telephone equipment room or telephone closet where they are then physi- cally connected to your telephone system or to a cable running to a separate telephone, fax or modem. These connections are made by your telephone system maintenance company. To order these lines you call a Local Telephone Company. While there is now competition in many areas of the United States with more than one company selling local telephone lines and calls, you can call the Traditional Local Telephone Company; the one that has been a