Animal handler, person who conducts animal training or is a wrangler
Handler, a sport coach, agent or promoter
Agent handling, person who manages a spy or agent of organizations in conflict such as nations and even groups and gangs involved in crusades, jihad, mass organized conversion rackets, etc.
Baggage handler, a person who loads and unloads baggage and other cargo for transport via aircraft
Mail handler, a postal worker
Aircraft handler, a branch of the Fleet Air Arm/Royal Navy
Garter handler, an old term for a pimp
Political handler, an advisor and supporter of a politician
Persons named Handler
Andrea Händler, Austrian actor and cabaret artist.
Carole Handler, American attorney
Chelsea Handler, American comedian and talk show host
Daniel Handler, American author and musician
Evan Handler, American actor
Evelyn Handler, 17th president of the University of New Hampshire
Phil Handler, American football player and coach
Rebecca Handler, American/Japanese actress
Ruth Handler, American businesswoman
Wolfgang Händler, German computer scientist
Computing
Handler, an asynchronous callback (computer programming) subroutine in computing
A particular class of service process in DNIX
A20 handler, the IBM PC memory manager software controlling access to the High Memory Area
Event handler, a routine for processing a programming event
Interrupt handler, a routine for processing CPU interrupts
Signal handler, a routine for handling signals sent to a process
Exception handling, a routine for handling software exceptions
Machines
Air handler, a device used as part of an HVAC (Heating, Ventilating, and Air Conditioning) system
Handler, a robotic device used to automatically place a device under test into an automatic test equipment system
Seismic Handler, an interactive analysis program for preferably continuous waveform data
Telescopic handler, a machine widely used in agriculture and industry
Arts and entertainment
"The Handler", a short story by Ray Bradbury
Handler (play), by Robert Schenkkan
The Handler (Har Mar Superstar album), the third CD from American singer Har Mar Superstar
Handler, a character class in Dragonlance
The Handler (TV series)
"The Handler", a song by British rock-band Muse on their 2015 album Drones (Muse album)