In simplest terms, computer telephony is the technique of coordinating the actions of telephone and computer systems. This technology has existed in commercial form since the mid-1980s, but it has been exploited only in a few niche markets -- particularly in large call centers, where call volumes easily justified the cost of complex custom-built systems. But in the 1990s, several factors have combined to significantly simplify computer-telephone systems and increase the marketplace's interest in computer telephony. International standards for interconnecting telephone and computer systems have been defined, notably the Computer-Supported Telephony Application (CSTA) call modeling and protocol standards from ECMA. Mass-market application programming interface (API) specifications have been heavily promoted by major market players such as Microsoft and Novell, and are gaining rapid acceptance. Voice processing technologies have advanced steadily, providing advanced features and high port densities at attractive prices. Public networks are offering more and more services which enable computer-telephone applications, such as Calling Line ID. And most important, the world economy is doing business over the telephone at an increasing rate, prompting business organizations to look for ways to make this process more efficient and economical.
