Feet Per Minute - a way of expressing velocity, epsecially climb/descent rates.
see MPH, furlongs per fortnight.
Airliners generally take-off and climb at about 500 FPM and gradually increase airspeed and climb rate, climbing as much as 4000 FPM to get several thousand feet above the surface, then reducing the rate until reaching cruising altitude.
In terms that the car-driving public can relate to, 250 FPM equals a little under 3 MPH. 10 MPH is 880 FPM.
Pilots in the US generally discuss rate-of-climb in FPM; the rest of the world uses meters per second (m/s). This can lead to some slight difficulties in communication, for instance among hang glider and paraglider pilots talking about flights and conditions. Luckily, there is a handy rule of thumb for converting from one to the other.
197 FPM = 1.00076 m/s, so considering 200 FPM equal to 1 m/s is reasonable for general purposes. This leads to a rule of "double it and multiply by 100" to convert from m/s to FPM. Conversely, "half it and divide by 100" works for going from FPM to m/s.
Note: Most modern rate-of-climb indicators (variometers), which work by detecting changes in air pressure, can be set to display in either FPM or m/s.
Soaring pilots like to know the strength of lift that other pilots are finding on a given day, or the range that is normal for a given site at a particular time of year and so on. A european pilot visiting a US site might ask about the lift and be told "Pretty good today, 500 up in the cores and only moderate sink in between." Seeing his blank look, the informed pilot can quickly add "That is, we're climbing at 2.5 meters per second in the thermals." and see the visitor grin in anticipation.
For hang gliders and paragliders, thermals that give indicated climb rates of 250-1000 FPM are great fun. Rates of 10-150 FPM require patience and concentration to "work" and avoid having to land. Rates over 1000 FPM are exciting, and soaring in desert thermals at upwards of 2000 FPM is not for the faint of heart. In still air, typical hang gliders and paragliders sink at 250 FPM, which is slow enough that one doesn't feel it but can see it if there are slopes or objects nearby for reference. 500 FPM sink is considered fast, and >750 FPM sink means one will be landing very soon. Note: HGs and PGs are landed by flying along the surface at zero FPM sink until one's momentum is used up.
Skydivers are understandably quite concerned with descent rates, and parachutes include nominal descent rate at a given load as part of their specifications. Hang glider and paraglider reserve parachutes (deployed if there is structural failure or some other catastrophe) are similarly rated, with a descent rate of 18 FPM (0.2 MPH) seen as the upper threshold for a "gentle" landing (impact), and rates up to 24 FPM (0.3 MPH) are deemed quite survivable.