Jan 11, 2018 - Have you ever been asked, “Can't you just use an API for that?” and thought to yourself “What the hell is an API?” Perhaps you started off. When to use API keys. You want to identify usage patterns in your API's traffic. You can see app usage in APIs & services. You want to be able to filter logs by API key. API keys cannot be used for: Identifying individual users — API keys don't identify users, they identify projects. Secure authorization.
Searches should include Wikipedia, which is surprisingly good for a number of programming concepts/terms such as:What is an API?An application programming interface (API) is a particular set of rules ('code') and specifications that software programs can follow to communicate with each other. It serves as an interface between different software programs and facilitates their interaction, similar to the way the user interface facilitates interaction between humans and computers.How is it used?The same way any set of rules are used.When and where is it used?Depends upon realm and API, naturally. Consider these:. (very useful;-). A.
which is often exposed as a C library. Core Windows system calls:.
The Classes and Methods in. The exposed by browsers to JavaScript., such as those provided by. An implementation of a protocol such asHappy coding.
Well, In addition to all the answers, I am just adding an example.As Others Said API stands for Application Programming Interface through which softwares can interact with each other. Note not a human interaction.Where it is usedAn example, You are buying an item in online through your credit card. You will provide credit card details and press continue button. It will tell you whether your information is correct or not. To provide these results, there are lot of things in the background.The application will send your credit card details to a remote application which will validate your information and send the result back your application. API is used in this scenario.I think hope it helps for the beginners who doesn't understand really what API is.ANOTHER EXAMPLEWeather applicationWithout API - Weather application must open weather.com site and read the details as human does.With API - Weather application will send a message to weather.com and receives the result and then display it.SOURCE Various online resources. Conaider this situation:Mark and Lisa are secretly a couple, and because of age difference they are not allowed to be together.
Mark and Lisa meet every night when nobody is watching. They have estabilished their own set of rules how to comunicate when the time comes. He stands in her garden and throws the small rock at her window.
Lisa knows that it is time, and responds by waving from the window and opening it afterwards so Mark can climb in. That was example how the API works.The rock is initial request to another end.
Another end waves, opens the window which basicaly means 'Welcome in!' .API is almost like human language but for computers. An API defines the interfaces by which one piece of software communicates with another at the source level. It provides abstraction by providing a standard set of interfaces - usually functions - that one piece of software (typically a higher-level piece) can invoke from another piece of software (usually a lower-level piece).For example, an API might abstract the concept of drawing text on the screen through a family of functions that provide everything needed to draw the text. The API merely defines the interface; the piece of software that actually provides the API is known as the implementation of the API.It is common to call an API a 'contract'.
This is not correct, at least in the legal sense of the term, as an API is not a two-way agreement. The API user (generally, the higher-level software) has zero input into the API and its implementation. It may use the API as-is, or not use it at all: take it or leave it!A real-world example of an API is the interfaces defined by the C standard and implemented by the standard C library. This API defines a family of basic and essential functions, such as memory management and string manipulation routines.