PACT was a series of compiler

Compiler

A compiler is a computer program that transforms source code written in a programming language into another computer language...

s for the IBM 701

IBM 701

The IBM 701, known as the Defense Calculator while in development, was announced to the public on April 29, 1952, and was IBM’s first commercial scientific computer...

 and IBM 704

IBM 704

The IBM 704, the first mass-produced computer with floating point arithmetic hardware, was introduced by IBM in 1954. The 704 was significantly improved over the IBM 701 in terms of architecture as well as implementations which were not compatible with its predecessor.Changes from the 701 included...

 scientific computers. Their development was conducted jointly by IBM and a committee of customers starting in 1954. PACT I was developed for the 701, and PACT IA for the 704. The emphasis in that early generation of compilers was minization of the memory footprint

Memory footprint

Memory footprint refers to the amount of main memory that a program uses or references while running.This includes all sorts of active memory regions like code, static data sections , heap, as well as all the stacks, plus memory required to hold any additional data structures, such as symbol...

, because memory was very expensive resource at the time. The word "compiler" was not in widespread use at the time, so most of the 1956 papers described it as an "(automatic) coding system", although the word compiler was also used in some papers.

See also

• Speedcoding
  Speedcoding
  Speedcoding or Speedcode was the first higher-level language created for an IBM computer. The language was developed by John Backus in 1953 for the IBM 701 to support computation with floating point numbers....
  
  , an interpreter for the 701
• FORTRAN
  Fortran
  Fortran is a general-purpose, procedural, imperative programming language that is especially suited to numeric computation and scientific computing...
  
  
• KOMPILER
  KOMPILER
  In computing, the KOMPILER was one of the first language compilation and runtime systems for International Business Machines' IBM 701, the fastest commercial U.S. computer available in 1955....
  
  
• SHARE
  SHARE (computing)
  SHARE Inc. is a volunteer-run user group for IBM mainframe computers that was founded in 1955 by Los Angeles-area IBM 701 users. It evolved into a forum for exchanging technical information about programming languages, operating systems, database systems, and user experiences for enterprise users...