In music, strumming is a way of playing a stringed instrument such as a guitar, ukulele, or mandolin. A strum or stroke is a sweeping action where a finger or plectrum brushes over several strings to generate sound. On most stringed instruments, strums are typically executed by a musician's designated strum hand (typically the musician's dominant hand, which is often responsible for generating the majority of sound on a stringed instrument), while the remaining hand (referred to as the fret hand on most instruments with a fingerboard) often supports the strum hand by altering the tones and pitches of any given strum.

Strums are often contrasted with plucking, as a means of vibrating an instrument's strings. In plucking, a specific string or designated set of strings are individually targeted to vibrate, whereas in strumming, a less precise targeting is usually used. Compared to other plucking techniques, any group of strings brushed in a single sweep by a plectrum could be considered a strum due to the plectrum's less precise string group targeting (however, a plectrum might simultaneously pluck a small group of strings without being considered a strum). In contrast, a musician could utilize a technique with more precise string group targeting (such as a fingerstyle or fingerpick technique) to pluck all the strings on a stringed instrument at once and this would still be considered a pluck, not a strum.