The keyboard world is full of confusing terminology and slang. This article provides a list of the terminology that may not be immediately obvious to outsiders. It can be used as a reference when you encounter something you don’t know, but may also act as jump start to get you into the scene or an inspiration for new ideas. I know I found a couple of new things while compiling this list.


Most definitions will be short and probably not entirely accurate. I also won’t link to external websites, if you want to investigate further, just search the web. A lot more in-depth information is widely available if you know what to search for (and with this dictionary, now you do).

40% - keyboard form factor that is only 12 keys wide and 4 keys high. A 40% keyboard only has an alphanumeric section and very limited space for non-alphabetic characters and special keys. Missing keys are accessed using layers.

60% - keyboard form factor that is 14 keys wide and 5 keys high. Compared to a full size keyboard, a 60% keyboard only has the full alphanumeric section including the number row. Special keys (like the function row and [PgUp] and [PgDn]) are accessed using layers.

65% - keyboard form factor that is 15 keys wide and 5 keys high. A 65% keyboard has a full alphanumeric section including a number row. On the right side there room for an extra column of 5 keys. This column differs between manufacturers, but it usually has at least [PgUp], [PgDn] and [Del] keys.

ABS - abbreviation for Acrylonitrile Butadiene Styrene, a plastic used for cheaper keycaps. When used for keycaps, ABS wears down under use, making the tops of the keycaps look polished and shiny. PBT is a more durable (and more expensive) material.

ANSI layout - standardized keyboard layout with a regular height [Enter] key, and the [Backslash] key above the [Enter] key. While generally considered to be the “American” layout, my experience is that this layout is also the most common in the Netherlands. The other standard keyboard layout is the ISO layout.

Artisan keycap - outrageously designed keycap. Artisan keycaps are often used as a keyboard decoration on the [Esc] key. Artisan keycaps come as transparent plastic with an encased figure or landscape, but also with complete 3D figures and scenes on top of the key.

BlueMicro - keyboard firmware, using the stock Arduino toolchain. BlueMicro has Bluetooth support for microcontrollers using Nordic’s nRF52832 and nRF52840 System on Chip. Other firmware alternatives are KMK, TMK, QMK and ZMK.

Choc - low profile switch produced by Kailh. Choc switches have a specific mount with two notches that will not accept a keycap with a regular MX stem.

Clicky switches - a keyboard switch with a audible “click” at the end of the travel. The other main key types are tactile switches and linear switches.

Colemak - a keyboard layout, designed in 2006, based on Qwerty that emphasizes on placing the most regularly used keys on the home row while leaving the positions of common computer shortcuts (cut, copy, paste, undo and select all) and the position of most non-alphabetic characters unchanged. A slight modification called Colemak-DH was later developed do address a couple of issues. Other alternative layouts are Dvorak and Workman.

Colemak-DH - a keyboard layout, based on Colemak with some minor adjustments. Most notably, on Colemak-DH, the frequently used [D] and [H] keys move to a more accessible location on the bottom row, straight below the index fingers.

Columnar - keyboard layout where the keys are aligned in straight columns, and the columns are offset to accomodate the different length of the fingers. Typically, without bending, all fingertips can rest on the home row keys.

Diode - an electronic component that allows current to flow in only one direction. Diodes are used in a keyboard matrix, to achieve N-Key rollover.

Double shot - method for producing keycaps by using separate molds for the legend and the key. The legend is not printed on the keycap, but a different color material all the way through the key. Double shot keycaps are very well suited for illuminated keys, by using a translucent material for the legend and an opaque material for the rest of the keycap.

DSA - a keycap family that uses the same side profile for all rows on the keyboard.

Dvorak - a keyboard layout patented in 1936 that emphasizes on using alternating hands for key sequences, and placing the most commonly used keys on the home row. Other alternative layouts are Colemak and Workman.

Endgame - the last keyboard you will ever buy or build, because it is magnificent, flawless and perfect in every way.

Ergogen - language to describe the layout of keys in JSON format, specialized for ergonomic and split keyboards. A couple of tools have been developed around this description language to generate plate definitions and PCB designs.

Filming - putting a thin plastic film between the top and bottom half of a keyboard switch to reduce rattling or generally make it feel more solid.

Full size keyboard - the most widely used, the “stock” keyboard form factor. A full size keyboard has an alphanumeric section, function keys, system keys, a navigation cluster, arrow keys and a numeric section for a total of over 100 keys.

Gasket mount - a keyboard design, when the plate is clamped between the top and bottom half of the case, with a dampening gasket.

Group buy - offer to produce a special product when enough people subscribe to buy. You’ll receive something special, but you probably need have patience.

Hand soldering - making all the necessary connections between the keyboard switches and the microcontroller by soldering wires.

Home row - the row of switches in the middle of the keyboard that your fingers touch when at rest. Usually, there is a homing key under both index fingers.

Home row mod - key mapping where some keys on the home row act as modifiers when held and as regular alphabet keys when tapped.

Homing key - a key that can be discerned from the other keys by touch and is used to find the position for the index fingers on the home row without looking. Usually there is a tangible small ridge on the bottom of a homing key.

Hotswap - the possibility to change keyboard switches without desoldering.

ISO layout - standardized keyboard layout with a larger [Enter] key, spanning 2 rows and the [Backslash] key to the left of the [Z]. The other standard keyboard layout is the ANSI layout.

KiCad - open source program used to design electric schema’s and PCB’s.

KLE - abbreviation for the website

KMK - open source firmware written in CircuitPython, requires a microcontroller that supports CircuitPython. KMK does not require a locally installed toolchain. The firmware can be installed by dropping a file in the root folder of the microcontroller, which will show up as a flash drive when connected to a PC. Other firmware alternatives are BlueMicro, TMK QMK and ZMK.

Layers - the metaphor used to give a key multiple functions. Activating a layer replaces the function of keys for different functions. The most common layer that everybody knows is activated by the [Shift] key. Typing the [9] key will give the number “9”. Holding down [Shift] activates a new layer. Now typing the [9] key gives the opening parentheses “(”. In custom keyboard configurations, the [Shift] layer is handled automatically, but other layers can be defined by the user.

Linear switches - a keyboard switch that gives the same linear resistance over its entire key travel. The other main key types are clicky switches and tactile switches.

Low profile switch - a switch that is both lower and has smaller key travel than a regular MX switch.

Matrix - a solution to reduce the required amount of wiring to connect switches to a microcontroller.

Mechanical keyboard - a keyboard where every key has its own individual high quality switch.

Membrane keyboard - a keyboard with a single rubber-like layer between the keys and a PCB to makes a connections when the user presses a key. There is a small gap between the rubber layer and the PCB. When a key is pressed, a conductive piece is pressed against the PCB, making the connection. This is the most commonly used keyboard type for cheaper desktop keyboards and for laptops.

Microcontroller - small PCB containing a microprocessor, a USB connection and some necessary circuitry to power and run the processor and make the (tiny) processor pins more accessible for connections.

Modifiers - keys that modify the behavior of other keys, like [Shift], [Alt] and [Ctrl].

MX - general designation for form the and dimensions of the most widely used mechanical switch. Originally created by Cherry, this is now the standard for almost all keyboard switches.

N-Key rollover - being able to press multiple keys at the same time, with exactly those keys registering correctly.

Ortholinear - keyboard layout where the keys are aligned in straight rows and columns. This as opposed to the more traditional staggered layout.

PBT - abbreviation for Polybutylene Terephthalate, a plastic used for keycaps. PBT is considered superior to the ABS alternative, but more expensive.

PCB - abbreviation for Printed Circuit Board, a usually green, non-conducting plate with electronic connections printed on both sides. A PCB can be used to pre-define all connections for a keyboard. A microcontroller is also a PCB.

Plate - the part of a keyboard that hold the switches in place. A plate is not strictly necessary, but usually part of a mechanical keyboard.

Poker - a 60% keyboard layout originally designed by the Vortex company. The Poker layout uses 6 mounting holes for the plate and PCB. The location of these mounting holes have more or less become the standard for 60% keyboard cases.

QMK - open source, customizable firmware project written in C. QMK firmware is written in C and requires a local toolchain installed on your PC. QMK has limited support for wireless keyboards. Other firmware options are BlueMicro, KMK, TMK and ZMK.

Qwerty - de facto standard layout of the alphabet keys on a keyboard, where the first letters on the top left row form the word “Qwerty”. This layout is an inheritance from the mechanical typewriter days. When hitting adjacent keys too quickly on a typewriter, the hammers would hit each other, causing malfunctions. The aim of the Qwerty layout was to avoid having adjacent keys for commonly used letter combinations. Common alternatives to the Qwerty layout are Dvorak, Colemak and Workman.

Rotary encoder - a rotating knob that can for instance be used for volume control.

Sandwich mount - a keyboard design, when the plate is clamped between the top and bottom half of the case (like a gasket mount, but without a dampening gasket).

Split keyboard - a keyboard that consists of two separate parts, one for each hand.

Stab (stabilizer) - mechanical construction used under the larger keys, like a spacebar, so it will depress smooth, even when pressed on one side. Stabs can be plate mounted (clicked onto the plate), or PCB mounted (either clicked or screwed). The screwed PCB mount stabs are considered the most stable.

Staggered layout - key layout inherited from ancient typewriters, where the keys from the back to the front of a keyboard are shifted left to right. On mechanical typewriters, the staggered layout ensured that the hammer that hits the paper was directly in line with the matching key. The opposite would be an Ortholinear layout.

Sublimated keycaps - a method for printing the legends on a keycap. Sublimation uses heat to engrave the legend into the keycap resulting in a very durable print. The more expensive method is double shot production. Sublimation can only be used on PBT keycaps and cannot be used for illuminated keys.

Tactile switches - a keyboard switch with a tangible “bump” in its travel. The other main key types are clicky switches and linear switches.

Tape mod - putting tape on the back of the PCB to make the typing sound more pleasing.

Tenkeyless - a keyboard form factor where, compared to a full size keyboard, the numberpad on the right is missing. A tenkeyless keyboard is less bulky, leaving more desk space for a mouse, while retaining most of the keys that people are familiar with.

Tenting - raising the middle side of both parts of a split keyboard to make it more comfortable.

TKL - abbreviation for tenkeyless

TMK - keyboard firmware, written in the C programming language. TMK requires a locally build toolchain. Other firmware alternatives are BlueMicro, KMK, QMK and ZMK.

Tray mount - a keyboard design, when the PCB and/or the plate are mounted to the bottom of the keyboard case.

Two shot - synonym for double shot

Vial - an open-source cross-platform (Windows, Linux and Mac) GUI and a QMK fork for configuring your keyboard in real time.

Workman - a keyboard layout, designed in 2010, that emphasizes on placing the most commonly used keys on the home row and considering which finger movements are comfortable. An important observation that Workman uses is that index fingers can comfortably bend inward, middle- and index fingers comfortably stretch out and pinky fingers won’t do either comfortably. Other alternative layouts are Colemak and Dvorak.

ZMK - an open source (MIT) keyboard firmware built on the Zephyrâ„¢ Project Real Time Operating System (RTOS). ZMK does not require a locally installed toolchain but instead runs in the cloud on GitHub Actions. Other firmware alternatives are BlueMicro, KMK, TMK and QMK.