Systems Programming Language, often shortened to SPL but sometimes known as SPL/3000, was a procedurally-oriented programming language written by Hewlett-Packard for the HP 3000 minicomputer line and first introduced in 1972. SPL was used to write the HP 3000's primary operating system, Multi-Programming Executive (MPE). Similar languages on other platforms were generically referred to as system programming languages, confusing matters.

Originally known as Alpha Systems Programming Language, named for the development project that produced the 3000-series, SPL was designed to take advantage of the Alpha's stack-based processor design. It is patterned on ESPOL, a similar ALGOL-derived language used by the Burroughs B5000 mainframe systems, which also influenced a number of 1960s languages like PL360 and JOVIAL.

Through the mid-1970s, the success of the HP systems produced a number of SPL offshoots. Examples include ZSPL for the Zilog Z80 processor, and Micro-SPL for the Xerox Alto. The latter inspired Action! for Atari 8-bit computers, which was fairly successful. The latter more closely followed Pascal syntax, losing some of SPL's idiosyncrasies.

SPL was widely used during the lifetime of the original 16-bit version of the HP 3000 platform. In the 1980s, the HP 3000 and MPE were reimplemented in an emulator running on the PA-RISC-based HP 9000 platforms. HP promoted Pascal as the favored system language on PA-RISC and did not provide an SPL compiler. This caused code maintenance concerns, and 3rd party SPL compilers were introduced to fill this need.

Hewlett-Packard introduced their first minicomputers, the HP 2100 series, in 1967. The machines had originally been designed by an external team working for Union Carbide and intended mainly for industrial embedded control uses, not the wider data processing market. HP saw this as a natural fit with their existing instrumentation business and initially pitched it to those users. In spite of this, HP found that the machine's price/performance ratio was making them increasingly successful in the business market.

During this period, the concept of time sharing was becoming popular, especially as core memory costs fell and systems began to ship with more memory. In 1968, HP introduced a bundled system using two 2100-series machine running HP Time-Shared BASIC, which provided a complete operating system as well as the BASIC programming language. These two-machine systems, collectively known as HP 2000s, were an immediate success. HP BASIC was highly influential for many years, and its syntax can be seen in a number microcomputer BASICs, including Palo Alto TinyBASIC, Integer BASIC, North Star BASIC, Atari BASIC, and others.

Designers at HP began to wonder "If we can produce a time-sharing system this good using a junky computer like the 2116, think what we could accomplish if we designed our own computer." To this end, in 1968 the company began putting together a larger team to design a new mid-sized architecture. New team members included those who had worked on Burroughs and IBM mainframe systems, and the resulting concepts bore a strong resemblance to the highly successful Burroughs B5000 system. The B5000 used a stack machine processor that made multiprogramming simpler to implement, and HP selected this same architecture for the new concept.

Two implementations were considered, a 32-bit mainframe-scale machine known as Omega, and a 16-bit design known as Alpha. Almost all effort was on the Omega, but in June 1970, Omega was canceled. This led to an extensive redesign of Alpha to differentiate it from the 2100s, and it eventually emerged with plans for an even more aggressive operating system design. Omega had intended to run in batch mode and use a smaller computer, the "front end", to process interactions with the user. This was the same operating concept as the 2000 series. However, yet-another-2000 would not be enough for Alpha, and the decision was made to have a single operating for batch, interactive and even real-time operation.