Borland's C compiler for IBM PCs.
Turbo C, version 1.0, was introduced by Borland in 1987. It offered the first integrated edit-compile-run development environment for C on IBM PCs. It ran in 384KB of memory. It allowed inline assembly, supported all memory models, and offered optimisations for speed, size, constant folding, and jump elimination.
Version 1.5 shipped on five 360 KB diskettes of uncompressed files, and came with sample C programs, including a stripped down spreadsheet called mcalc.
Turbo C 2.0 has a debugger, a fast assembler, and an extensive graphics library.
Turbo C has been largely supplanted by Turbo C++, introduced circa September, 1990 for both MS-DOS and Microsoft Windows.
["Compiling the facts on C", Richard Hale Shaw, PC Magazine, September 13, 1988, pages 115-183].