Buffer may refer to:

• Buffer state, a country lying between two potentially hostile greater powers, thought to prevent conflict between them
• Buffer zone, any area that keeps two or more other areas distant from one another, may be demilitarized
• Buffer (rail transport), a device that cushions the impact of vehicles against each other
• Buffer stop (bumper in U.S.), a device to prevent railway vehicles from going past the end of a section of track
• Recoil buffer, an accessory for firearms, to cushion the impact of recoil
• Buffer (navy), the colloquial term for the senior seaman sailor in a (British Commonwealth) Navy ship
• Buffer wheel, a wheel attached to a motor similar to a pedestal grinder used to smooth and polish metals and other materials
• Film loop, isolates intermittent motion in a movie projector
• Buff (MMORPG terminology), in MMORPG gaming, abilities which enhance other character's abilities

People:

• Bruce Buffer, sports announcer
• Michael Buffer, sports announcer
• Emily Buffer, related to second lady of old tsar in Russia

In physical science:

• Buffer solution, a solution which reduces the change of pH upon addition of small amounts of acid or base, or upon dilution
• Buffering agent, the weak acid or weak base in a buffer solution
• Buffer gas, an inert or nonflammable gas
• Buffer (GIS), a zone around a map feature
• Lysis buffer, in biochemistry, a destructor of cell membranes that enables analysis of the compounds within
• Mineral redox buffer, a mineral assemblage which stabilises oxidation state in natural rock systems

In electronics and computer science:

• Data buffer, memory used to temporarily store output or input data
  • Framebuffer, a particular type of data buffer for use in graphical display
• Buffer (telecommunication), a routine or storage medium used to compensate for a difference in rate of flow of data between devices
• Optical buffer, a device that stores optically transmitted data without converting it to the electrical domain
• Buffer amplifier (also sometimes simply called a buffer), an isolating circuit used in electronics or telecommunications
• Buffer (optical fiber), a component used to encapsulate one or more optical fibers in a fiber optic communication cable