What (who) is TOPS-20 - definition

OPERATING SYSTEM BY DIGITAL EQUIPMENT CORPORATION

TWENEX; Tops-20; Twenex; TOPS 20; Decsystem 20; DecSystem 20; PA1050

TOPS-20

TWENEX

TWENEX

<operating system> /twe'neks/ The TOPS-20 operating system by DEC - the second proprietary OS for the PDP-10 - preferred by most PDP-10 hackers over TOPS-10 (that is, by those who were not ITS or WAITS partisans). TOPS-20 began in 1969 as Bolt, Beranek & Newman's TENEX operating system using special paging hardware. By the early 1970s, almost all of the systems on the ARPANET ran TENEX. DEC purchased the rights to TENEX from BBN and began work to make it their own. The first in-house code name for the operating system was VIROS (VIRtual memory Operating System); when customers started asking questions, the name was changed to SNARK so DEC could truthfully deny that there was any project called VIROS. When the name SNARK became known, the name was briefly reversed to become KRANS; this was quickly abandoned when someone objected that "krans" meant "funeral wreath" in Swedish (though some Swedish speakers have since said it means simply "wreath"; this part of the story may be apocryphal). Ultimately DEC picked TOPS-20 as the name of the operating system, and it was as TOPS-20 that it was marketed. The hacker community, mindful of its origins, quickly dubbed it TWENEX (a contraction of "twenty TENEX"), even though by this point very little of the original TENEX code remained (analogously to the differences between AT&T V6 Unix and BSD). DEC people cringed when they heard "TWENEX", but the term caught on nevertheless (the written abbreviation "20x" was also used). TWENEX was successful and very popular; in fact, there was a period in the early 1980s when it commanded as fervent a culture of partisans as Unix or ITS - but DEC's decision to scrap all the internal rivals to the VAX architecture and its relatively stodgy VMS OS killed the DEC-20 and put a sad end to TWENEX's brief day in the sun. DEC attempted to convince TOPS-20 users to convert to VMS, but instead, by the late 1980s, most of the TOPS-20 hackers had migrated to Unix. [Jargon File] (1995-04-01)

Top 20 on 20

RADIO STATION

20 on 20

Top 20 on 20 (or just 20 on 20) was a commercial-free, interactive hit music satellite radio station. It was on channel 3 (previously 20) on Sirius XM Radio.

https://en.wikipedia.org/wiki/Top_20_on_20

Wikipedia

TOPS-20

The TOPS-20 operating system by Digital Equipment Corporation (DEC) is a proprietary OS used on some of DEC's 36-bit mainframe computers. The Hardware Reference Manual was described as for "DECsystem-10/DECSYSTEM-20 Processor" (meaning the DEC PDP-10 and the DECSYSTEM-20).

TOPS-20 began in 1969 as the TENEX operating system of Bolt, Beranek and Newman (BBN) and shipped as a product by DEC starting in 1976. TOPS-20 is almost entirely unrelated to the similarly named TOPS-10, but it was shipped with the PA1050 TOPS-10 Monitor Calls emulation facility which allowed most, but not all, TOPS-10 executables to run unchanged. As a matter of policy, DEC did not update PA1050 to support later TOPS-10 additions except where required by DEC software.

TOPS-20 competed with TOPS-10, ITS and WAITS—all of which were notable time-sharing systems for the PDP-10 during this timeframe.

https://en.wikipedia.org/wiki/TOPS-20

Examples of use of TOPS-20

1. Campaigning in eastern Saxony–Anhalt, where unemployment tops 20 percent, Merkel argued Friday for tax breaks and reductions in red tape to encourage smaller firms to create jobs.

2. Campaigning in eastern Saxony–Anhalt, where unemployment tops 20 percent, Merkel argued Friday for tax breaks and reductions in red tape to encourage smaller firms to create jobs. Part of the paperwork belongs in the trash,‘‘ she told about 1,000 people at a rally in Dessau. Saxony–Anhalt cannot be governed from a rocking–chair, it needs new energy,‘‘ retorted Social Democrat Vice Chancellor Franz Muentefering at an event in nearby Magdeburg.