Job Queue / Task Queue / Message Queue

Gearman :

Job Queue
Client <-> Gearman <-> Worker
Synchronize, Asynchronous

ZeroMQ :

Message Queue and Socket Programming

Celery :

write in Python
no client and worker
queuing task and do task in background
Celery + RabbitMQ for "data" queue in Instragram
Celery doing task and queuing data in RabbitMQ

RabbitMQ :

Message Queue
Work queues : Publish (task) / Subscribe (worker)

Queues

http://queues.io/

Gearman and ZeroMQ, two different animals
https://speakerdeck.com/coudenysj/gearman-and-zeromq-two-different-animals

Messaging at Scale at Instagram by Rick Branson

https://speakerdeck.com/pyconslides/messaging-at-scale-at-instagram-by-rick-branson