Chef:

• Has a client and server architecture. Apart from a Chef Client and Server, there is one another important component called a Chef Workstation.
• The Chef workstation and Chef client could be windows or Linux/Unix MACHINES, but the Chef server supports only Linux/Unix.
• The Chef configuration management tool is in the market for a long time hence is stable, mature and has GOOD community support
• Chef uses the pull configuration
• Chef uses an imperative language written using the ruby DSL (Domain SPECIFIC Language)
• Chef uses a command-line tool called knife for communication.
• Ideal for developers with advanced programming skills

Puppet:

• Has an agent/master architecture.
• Puppet agent supports both Windows and Linux/Unix whereas puppet master support only Linux/Unix
• Puppet is also in the market for a long time hence is stable, mature and has good community support
• Puppet also uses the pull configuration
• Puppet uses a declarative language written using the puppet DSL (Domain Specific Language)
• Puppet uses SSL (Secure sockets layer) for communication
• Ideal for developers with less programming skills

Ansible:

• Ansible is AGENTLESS where no software needs to be  installed on client systems.
• Ansible server supports only Linux/Unix
• Ansible is a NEW player in the market but shows a promising growth trend
• Ansible uses the push configuration
• Ansible uses YAML (Ain’t Mark-up Language)
• Ansible uses SSH(Secure socket shell) for communication
• Ideal for developers with basic programming skills