Deathmatch (from the English term meaning "a match to the death") is a mode in CS2 with no rounds, bomb, or economy: a player spawns on the map, kills opponents or dies, and then almost immediately respawns at a new point with a new weapon. The single goal is to rack up as many kills as possible in the allotted time. Unlike ranked matches, no one "loses the round" by dying: death simply restarts the cycle, so dozens of short engagements can happen within a short session.
This format has existed in shooters for decades, and in CS2 it's used primarily as a warm-up before playing or as a way to target specific mechanics: aiming at moving targets, getting used to weapon recoil, and reaction speed to an opponent appearing on screen. The built-in CS2 deathmatch server typically also highlights damage and hits, which is useful for immediate feedback — unlike a regular match, where such information isn't available in the moment.
The problem most often raised by those analyzing newcomers' progress is that deathmatch easily turns into an aimless activity. If you go in without a specific goal — just "shooting around" — the training barely transfers to ranked play, where not just reflexes matter but also positioning, reading the round, and teamwork. Deathmatch doesn't teach tactics, communication, or map understanding — it isolates and improves aim mechanics and reaction speed, and even that only works if the player sets a concrete goal, such as practicing a specific weapon or movement type, rather than just farming frags.
For this reason, deathmatch is most often recommended as a warm-up tool rather than the main instrument of growth: a few minutes before a session of ranked games to "warm up the hand," not a replacement for reviewing one's own mistakes or studying tactics. The term itself has taken root in the Russian-speaking community without translation — "deathmatch" and the shortened "DM" are used with equal frequency, and both are understood without explanation in any game chat.