Definitions

Hybrid-cloud

• Ability and flexibility of running parts or all of your cloud solution and services on premise and / or on a public cloud
• Flexible deployment of cloud services into various topologies (public / public, public / private, private / private and so on)
• Choice in deployment and management of cloud services

An open hybrid cloud combines and unifies public cloud and private cloud services from multiple cloud vendors to create a single, flexible IT infrastructure, based on open source technologies. Learn more about What is Hybrid Cloud?.

Multi-cloud

• Running parts or all of a cloud solutions in multiple clouds.
• Ability and flexibility to move certain parts of a cloud solution to different cloud providers.
• The opposite of mono-cloud.

https://developer.ibm.com/videos/mutlicloud-for-developers-an-introduction/

Lock-in and lock-down

• A condition in which continuing to use the cloud software or services requires you to select one specific cloud provider
• Cloud software that can be used with specific cloud or cloud services
• The opposite of open

Open Source Software

• Planning and building of software in the open with resulting artifacts available to all
• Open governance to allow all to participate in all aspects of the development and planning
• Using a license that allows software to be used, modified, embedded and sold by anyone

Inner-Source Software

• Building software with intention of OSS
• Keeping governance and planning in house
• Releases done in the open