MSMQ vs ZeroMQ: What are the differences?
MSMQ: A technology for asynchronous messaging. This technology enables applications running at different times to communicate across heterogeneous networks and systems that may be temporarily offline. Applications send messages to queues and read messages from queues; ZeroMQ: Fast, lightweight messaging library that allows you to design complex communication system without much effort. The 0MQ lightweight messaging kernel is a library which extends the standard socket interfaces with features traditionally provided by specialised messaging middleware products. 0MQ sockets provide an abstraction of asynchronous message queues, multiple messaging patterns, message filtering (subscriptions), seamless access to multiple transport protocols and more.
MSMQ and ZeroMQ can be primarily classified as "Message Queue" tools.
ZeroMQ is an open source tool with 5.34K GitHub stars and 1.57K GitHub forks. Here's a link to ZeroMQ's open source repository on GitHub.