Editing PDP-8 (section)

==Programming facilities==
Early PDP-8 systems were shipped with no pre-installed software; each time the PDP-8 was powered up, the user hand-entered instructions using a bank of 12 toggle switches. Typically, these instructions were a [[Booting|bootstrap loader]] to read a program from the paper tape reader. Program development could then proceed, using paper tape input and output.

Paper-tape versions of a number of programming languages became available, including DEC's [[FOCAL (programming language)|FOCAL]] interpreter<ref name=focalmanual>{{cite book|url=http://www.bitsavers.org/www.computer.museum.uq.edu.au/pdf/DEC-08-AJAB-D%20PDP-8-I%20FOCAL%20Programming%20Manual.pdf|title=FOCAL Programming Manual for PDP-8, PDP-8/S, PDP-8/I, LAB-8, LINC-8|publisher=Digital Equipment Corporation|id=DEC-08-AJAB-D|year=1968}}</ref> and a 4K [[FORTRAN]] compiler and runtime.

Toward the end of the PDP-8 era, operating systems such as [[OS/8]] and COS-310 allowed a traditional [[line mode]] [[text editor|editor]] and command-line [[compiler]] development system using languages such as PAL-III assembly language, FORTRAN, [[BASIC]], and [[DIBOL]].

Fairly modern and advanced [[real-time operating system]] (RTOS) and [[preemptive multitasking]] multi-user systems were available: a real-time system (RTS-8) was available as were multiuser commercial systems (COS-300 and COS-310) and a dedicated single-user word-processing system (WPS-8).

A [[time-sharing]] system, [[TSS-8]], was also available. TSS-8 allows multiple users to log into the system via 110-baud terminals, and edit, compile and debug programs. Languages include a special version of BASIC, a FORTRAN subset similar to FORTRAN-1 (no user-written subroutines or functions), an [[ALGOL]] subset, FOCAL, and an assembler called PAL-D.

A fair amount of user-donated software for the PDP-8 was available from [[DECUS]], the Digital Equipment Corporation User Society, and often came with full source listings and documentation.