Services provided through a library or similar institution need to be easy to apply by using each person and in any shape. maximum services, but, can best be used within the fixed context of a selected user interface (UI). If a service is also handy thru software programming interface (API), its capability may be integrated and used in other applications, too. alas the want to expose services thru open APIs is less apparent than UIs.
User interfaces are curated and revised by usability studies and person experience (UX) at excellent. In different instances the UI is clearly judged with not unusual experience through everyday library body of workers and control. AngularJS APIs on the other hand, can't really be considered, used, and judged by way of everyone. in contrast to the UI, an API isn't a very last application to utilize a carrier, but the basis for introduction of provider programs: with out APIs, applications are hard to build and services can simplest be supplied in confined shape. with out applications, however, it's far difficult to justify the need for an API.