It is part of the T-carrier system, originally developed for the transmission of multiple telephone calls over copper lines, but later adapted for data communications. 

• High Bandwidth Capacity: DS3 provides a high-capacity bandwidth of 44.736 Mbps, which is equivalent to 28 T1 lines. Each T1 line in this context carries 1.544 Mbps, and a DS3 line bundles these together.

• Use in Telecommunications: DS3 lines are commonly used by businesses, ISPs (Internet Service Providers), and telecommunications companies to transmit large amounts of voice and data traffic.

• Data Transmission: Due to its high bandwidth, DS3 is suitable for transmitting large data files, video conferencing, and handling high volumes of internet traffic.

• Cost Considerations: Due to the infrastructure required, DS3 lines are generally more expensive than traditional T1 lines and are usually adopted by organizations with substantial data transfer needs.

DS3 lines represent a significant step in the evolution of digital data transmission technologies, offering high-capacity bandwidth for intensive data and voice communication needs.