how does an API Work code example

Example 1: what is an api

An application program interface (API) is a set of routines, protocols, and
tools for building software applications.

Basically, an API specifies how software components should interact.
Additionally, APIs are used when programming graphical user interface (GUI)
components.

A good API makes it easier to develop a program by providing all the
building blocks. A programmer then puts the blocks together.

Example 2: How does Math.ceil work

Math.ceil(x); //This equals the next whole number after x. X must be a double.

//Example use:
x = Math.ceil(x);
//Now x is equal to x rounded up.

Example 3: what is an api

An application programming interface (API) is a computing interface which
defines interactions between multiple software intermediaries.

It defines the kinds of calls or requests that can be made, how to make them,
the data formats that should be used, the conventions to follow, etc.

Example 4: does boxshadow work

.shadow {
  -moz-box-shadow:    3px 3px 5px 6px #ccc;
  -webkit-box-shadow: 3px 3px 5px 6px #ccc;
  box-shadow:         3px 3px 5px 6px #ccc;
}

Example 5: what is an api

=> On a bare minimum explanation, API are function prototypes which enable the
   user to use the functionality of any component by making a function call 
   without revealing the internal workings of the component.

=> It is a mode of abstraction from the lower layers of software stack , so as 
   to only provide service when needed for higher layers.

=> An API can manifest in many forms, it can be a simple function call in C,
   it can be web service API such as Twitter or FB API, it can be a library call
   to OS kernel, or can be an interrupt routine.


=> API can be just a standalone call or in form of libraries. API are part 
   and parcel of software interaction and data transfer.

Hope this clarifies.