A lettermark keeps just two or three initials from the brand name and drops the rest — a fix for names that are long or made of several words (say, "Meridian Kite Company") and don't read well as a wordmark at small sizes.
The initials usually sit inside a simple container — a circle, a square — to anchor their weight, and the point where two letters touch or overlap gets refined, almost like a ligature, so they read as one mark rather than two separate letters. Initials alone rarely say what the brand actually does, so first-time exposure should always pair the mark with the full name.
It's strongest in small, near-square spaces — favicons, app icons, social profile photos. The catch is that initials run out fast: before locking one in, it's worth checking whether a competitor in the same space already owns the same two letters.
When to use
Use it when the name is long or multi-word and struggles to read in tight spaces like favicons or app icons. Always show it alongside the full name on first exposure.