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Chris HoffmanEditor-in-Chief

Chris Hoffman is Editor-in-Chief that How-To Geek. He"s created about an innovation for end a decade and was a PCWorld columnist for 2 years. Chris has actually written for The brand-new York Times, been interviewed together a an innovation expert on TV stations favor Miami"s NBC 6, and also had his work covered by news outlets prefer the BBC. Because 2011, Chris has actually written over 2,000 short articles that have been read virtually one billion times---and that"s just right here at How-To Geek. Read more...

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UpdatedAug 24, 2021, 1:34 afternoon EDT| 2 min read
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Glance at her keyboard and also chances are you’ll view a few keys you never use close to the top-right corner: Sys Rq, scroll Lock, and Pause / Break. Have actually you ever wondered what those secrets are for?

While these keys have been gotten rid of from some computer system keyboards today, they’re tho a usual sight — also on new keyboards.

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Sys Rq

The SysRq vital (sometimes Sys Req) is one abbreviation for system Request. These days, keyboards generally incorporate the SysRq an essential with the Print display (or Prt Scr) key. To in reality invoke the device Request key, you’d have to press Alt+SysRq.

This key was meant for invoking low-level operating mechanism functions. It behaves differently from other secrets on your keyboard — as soon as you press this key, your computer’s BIOS generates a unique interrupt that tells the operating system the crucial was pressed. The operating system can listen because that the event and do other special.

These days, many operating systems and also programs will certainly simply disregard this key-press event. One notable exemption is Linux, wherein the “Magic SysRq key” have the right to send regulates directly come the Linux kernel to help recover from crashes and debug the operation system.

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Scroll Lock

Scroll Lock is a toggle, as with Caps Lock and also Num Lock — on part keyboards, role Lock may also have a dedicated light.


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Scroll Lock to be designed for older, text-mode environments, which had a small amount of available screen space. Pushing the arrow keys typically moved the text-entry cursor around, yet people want a way to scroll up and also down v the components of a text screen.

When role Lock was enabled, the arrow keys would certainly scroll the components of the display instead of moving the cursor.

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With modern graphical environments that encompass scroll bars and also mouse wheels, this habits is no longer important — in fact, many programs will overlook the scroll Lock an essential entirely.

One notable program that continues to obey role Lock is Microsoft Excel. Once Scroll Lock is enabled in Excel, pressing the arrowhead keys will scroll the city hall area without relocating the cursor.

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Pause / Break

The Pause and Break secrets were used in DOS and still role in the Command prompt today.


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The Pause vital is draft to pause a text-mode program’s calculation — it still functions in the Command Prompt home window on Windows. Once you push Pause, the output scrolling under your screen will stop. Depending upon how the routine is written, this may also pause the program’s execution. Push another crucial after pausing and also the regime will continue.

The Pause vital can also pause many computers during the BIOS boot-up process. This can allow you to read BIOS article (power-on self-test) messages that flash ~ above your screen for a brief time.

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Image Credit: Thiago Avancini on Flickr

The Break crucial can be offered to end DOS applications — pushing Ctrl+Break terminates a DOS application. This faster way functions likewise to Ctrl+C, which is also used to terminate applications in command-line environments.

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These secrets are old and also not commonly used — if friend wondered that was utilizing them, the prize is very couple of people. With the exception of the scroll Lock key in Microsoft Excel, there’s very tiny the average person can do with these keys. In fact, it’s surprising the they’re quiet so common on key-boards today.


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Chris HoffmanChris Hoffman is Editor-in-Chief that How-To Geek. He"s written about technology for end a decade and was a PCWorld columnist for 2 years. Chris has actually written because that The brand-new York Times, been interviewed as a technology expert ~ above TV stations like Miami"s NBC 6, and had his job-related covered by news outlets like the BBC. Because 2011, Chris has written end 2,000 short articles that have been read nearly one billion times---and that"s just below at How-To Geek. Read full Bio »