Interoperability is a technical mechanism for computing systems to work together, even if they are from competing firms. Well-known examples of interoperability include e-mail, and telephone voice and messaging services — you can send an e-mail or text message or call anyone else, regardless of the service providers, apps or devices you use.
In contrast, social media services like Facebook or Twitter, messaging apps, smartphone app stores, and many other digital services today tend to only support interactions within their own platforms. A Facebook user cannot follow someone else’s Twitter feed, a Telegram user is blocked from joining a WhatsApp group, and an iPhone user can only use apps that have been pre-approved by Apple’s own app store. This requires consumers to adopt cumbersome workarounds or use multiple applications and devices that are incompatible with each other.
Interoperability is one of the basic principles on which the internet was built. By adopting open technical standards, people and companies around the world started to communicate and exchange services and content in a simple and effective way. Breaking down that network into ‘walled gardens’ controlled by a single company is the dream of aspiring monopolists; but it breaks the very principle that allowed the internet to thrive and foster growth and development for all its participants.