What is API?
Application Programming Interface. Think of a waiter who takes your order (request) and brings the food (data) from the kitchen (server).
API stands for Application Programming Interface, but the best explanation is the waiter at a restaurant. You sit at the table and want food, but you do not walk into the kitchen and cook it yourself. Instead you give your order to the waiter (that is the API), who takes it to the kitchen (the server) and comes back with the food (the data). The API is the messenger between you and the system doing the work.
In practice, an API is a set of rules for how two programs talk to each other. Thanks to APIs, different systems can share information without needing to know exactly how the other works inside — just as you do not need to know how to cook the meal to order it. You only need to know what you can ask for, and the waiter handles the rest.
APIs are the glue holding the modern digital world together. Almost every app you use talks to other systems via APIs in the background.
Why are APIs important for your business?
APIs let your different systems talk to each other automatically instead of you moving data by hand. Your online shop can send orders straight to accounting, your booking page can fetch available slots from the calendar, and the customer database can update without manual typing. That saves time and reduces errors.
They also open the door to new features. Want to show shipping prices, take card payments, or embed a map? It all happens via APIs to services that have already solved it for you.
APIs in practice
Say you run an online shop. When a customer pays, your site talks via an API to a payment service like Stripe, which handles the transaction and sends back a response: approved or declined. At the same time, another API can tell the courier that a parcel needs collecting. All of this happens in seconds, without you lifting a finger.
The point is you do not have to build everything yourself. Via APIs you borrow functionality from specialists and connect it into a smooth whole.
Common questions about API
What does API mean?
API stands for Application Programming Interface. It is a set of rules that lets two programs talk to each other and exchange information — like a waiter who takes your order to the kitchen and brings back the food.
What is an API used for?
An API connects different systems so they can share data automatically. For example, your online shop can send orders to accounting, take payment via a payment service, or fetch shipping prices — all via APIs.
Does my business need an API?
If you want your systems to talk to each other without manual work, or to plug in services like payments and shipping, APIs are the key. Most modern websites and apps use APIs in the background.
Related terms
Serverless
There are still servers — you just do not need to worry about them. Someone else has the headache. You have the app.
Cache
Stored data that loads instantly instead of being fetched again. Often the reason your site feels fast — or why changes do not show up.
CDN
Content Delivery Network — copies of your site spread around the world so it loads quickly wherever your visitors are.
Cloud
Someone else's computers. Servers in massive data centres you rent instead of own — AWS, Google Cloud, Azure.
Database
Where all your data lives — users, orders, everything. Lose the database and you lose everything, which is why we back it up.
DNS
The internet's phone book. Translates zorc.se into an IP address so your browser finds the right server.