Software

Hamlib is a software library and was create to simplify computer control for amateur radio.

Fldigi is a computer program intended for Amateur Radio Digital Modes operation using a PC. Fldigi  uses the PC sound card as the main means of input from the radio, and output to the radio. These are audio-frequency signals. The software also controls the radio by means of another connection, typically a serial port.

Fldigi is multi-mode, which means that it is able to operate many popular digital modes without switching programs, so you only have one program to learn. Fldigi includes all the popular modes, such as DominoEX, MFSK16, PSK31, and RTTY.

CQRLOG is an advanced ham radio logger based on MySQL database. Provides radio control based on hamlib libraries (currently support of 140+ radio types and models), DX cluster connection, online callbook, a grayliner, internal QSL manager database support and a most accurate country resolution algorithm based on country tables developed by OK1RR. CQRLOG is intended for daily general logging of HF, CW & SSB contacts and strongly focused to easy operation and maintenance.

WSJT-X is a computer program which implements communication protocols or "modes" called FT8, JT4, JT9, JT65, QRA64, ISCAT, MSK144, and WSPR, as well as one called Echo for detecting and measuring your own radio signals reflected from the Moon.  These modes were all designed for making reliable, confirmed QSOs under extreme weak-signal conditions.