API
Interface for connecting systems
An API (Application Programming Interface) is the interface through which two software systems communicate. One system sends a request in an agreed format and the other returns a response with data or performs an action. Thanks to APIs, applications exchange data without human intervention.
How an API works
An API works on a request-and-response principle. Your application sends a request to a precise address, for example “give me the status of order number 123”. The other system processes the request and returns a response in a structured format, most often JSON. Both sides follow agreed rules, so they always understand each other.
Importantly, an API hides the internal complexity of a system. You don’t need to know how the other application is built or where it keeps its database. You only need to know what request to send and what response to expect. That is exactly why APIs can connect systems from different vendors.
What APIs are used for
APIs are the backbone of the modern web. Through an API a site shows the current exchange rate, a map, the weather, or a payment gateway. An e-shop sends orders to a warehouse system, an invoicing app pulls data from a bank, and a booking form writes appointments into a calendar.
For a business this means individual tools don’t have to work in isolation. With custom software development we connect your systems through APIs, which removes the manual rekeying of data, lowers the error rate, and lets processes run automatically.
- Connecting an e-shop to accounting, a warehouse, or a carrier.
- Integrating a payment gateway or sign-in with Google.
- Linking the website with a CRM and marketing tools.
- Accessing data from external services such as maps or rates.
Public and private APIs
Large services offer public APIs so that third-party applications can connect to them, for example payment gateways or map data. Private APIs are built by a company for its own systems so they can communicate securely. Access to them is usually protected by an authentication key.
Need to connect your systems?
Explore custom developmentFrequently asked questions
Do I need an API for my website or e-shop?
If you want to connect the site to other systems, for example accounting, a warehouse, a CRM, or a payment gateway, you need an API. It saves time by removing manual data rekeying and lowers the error rate. For a simple presentation with no integrations you don’t need one.
Is connecting through an API secure?
Yes, when it is designed properly. Communication runs over an encrypted connection and access is verified with an authentication key or token. The key is to limit who can reach which data and to review those permissions regularly.
Can it connect to a system we already use?
In most cases yes. If your current application has an API, we can connect to it. If it doesn’t, the needed interface can usually be developed. With custom development we are happy to assess which integrations are possible in your case.