Units - The length of each cap is determined by “units”. Shown as the number of units followed by a lowercase “u” most of the time. All the alphabetical caps are 1u.

Legends - The letters or icons on the actual keycap.

Sublegends - Legends that are secondary to the main legend. Usually another language.

Stepped Keys - Caps that have a step on the right side of them.

Sculpt/Sculpted - Some keycaps are different heights and angles on each row to create a sculpted profile for a more comfortable typing experience. You will often see numbers assigned to each height/angle to quickly show you the sculpt of the keycap set. (Ex: 1-2-3-4-4)

Uniform - When a profile is the same angle and height on each row to create a uniform typing experience with no sculpt. A common uniform profile is DSA.

Rows - Each row of a sculpted profile is numbered. R1-R4 are the standard rows but some sets include row R0-R5.

Cylindrical - This describes keycap profiles where the top of the keycap where your finger touches is "cutout" of the cap in the shape of a cylinder on its side. The most popular cylindrical profile is Cherry.

Spherical - This describes keycap profiles where the top of the keycap where your finger touches is "cutout" of the cap in the shape of a sphere on its side. The most popular cylindrical profile is SA.