Loog is a guitar company founded in 2011 by Rafael Atijas, built around three-string guitars designed to make learning easier for children and beginners. The concept originated from Atijas's master's thesis at NYU and launched via Kickstarter, with a follow-up 2019 campaign that became one of the highest-funded guitar projects in Kickstarter history. The lineup spans kid-sized acoustic and electric models (Loog Mini, Loog Pro), adult three-string guitars, ukuleles, and a small digital piano, paired with a companion app that teaches chords, tablature, and licensed songs.

The three-string format — tuned to the first three strings of a standard guitar — lets players form chords with a single finger and transfer what they learn to a standard six-string. Loog has released co-branded collections with Fender, Gibson, The Beatles, and Hello Kitty, alongside its core acoustic, electric, and mini guitar lines. The brand occupies a distinct niche between traditional instrument makers and educational toys, and has been adopted by families as well as by well-known musicians including Jack White and members of The Rolling Stones.

Loog has 6 products cataloged on Equipboard, including Solid Body Electric Guitars, Beginner Kits, and Beginner Kits. Their gear is featured by 2 artists, with the strongest followings in Hip Hop, Jazz, and Rock. Notable users include Steve Terryberry and Headnodic.