What Is a REST API? A Plain-Language Guide From Kathmandu, Nepal

REST API is a term that comes up often in the technical proposals we write for clients in Kathmandu, Nepal, and it is simpler than it sounds. REST is simply a set of conventions for how one piece of software asks another for data or tells it to do something, over the same basic protocol that powers the web. A REST API exposes specific 'endpoints,' addresses that a program can request information from or send information to, similar to how a browser requests a web page.

The reason REST APIs matter to a business owner is that they define what your website can connect to. When we say a mobile app 'talks to' the same backend as your website, we mean both are using the same REST API to read and write the same underlying data, which keeps everything consistent.

You do not need to understand the technical details to make good decisions, but it helps to know that a well-documented, properly structured API makes future integrations, a mobile app, a partner's system, a new payment provider, much easier and cheaper to build. A messy or undocumented API quietly taxes every future project that touches it.