### What is API?
Application Programming Interface
The term API is an acronym, and it stands for “Application Programming Interface.”
Think of an API like a menu in a restaurant. The menu provides a list of dishes you can order, along with a description of each dish. When you specify what menu items you want, the restaurant’s kitchen does the work and provides you with some finished dishes. You do not know exactly how the restaurant prepares that food, and you do not really need to.
Similarly, an API lists a bunch of operations that developers can use, along with a description of what they do. The developer doesn’t necessarily need to know how, for example, an operating system builds and presents a “Save As” dialog box. They just need to know that it’s available for use in their app.
This isn’t a perfect metaphor, as developers may have to provide their own data to the API to get the results, so perhaps it’s more like a fancy restaurant where you can provide some of your own ingredients the kitchen will work with.
But it’s broadly accurate. APIs allow developers to save time by taking advantage of a platform’s implementation to do the nitty-gritty work. This helps reduce the amount of code developers need to create, and also helps create more consistency across apps for the same platform. APIs can control access to hardware and software resources.
APIs Are Used for Communication Between Services
APIs are used for all kinds of other reasons, too. For example, if you have ever seen a Google Maps object embedded on a website, that website is using the Google Maps API to embed that map. Google exposes APIs like this to web developers, who can then use the APIs to plop complex objects right on their website. If APIs like this did not exist, developers might have to create their own maps and provide their own map data just to put a little interactive map on a website.
And, because it’s an API, Google can control access to Google Maps on third-party websites, ensuring they use it in a consistent way rather than attempting to messily embed a frame that shows the Google Maps website, for example.
This applies to many different online services. There are APIs for requesting text translation from Google Translate, or embedding Facebook comments or tweets from Twitter on a website.
Amazon API
Amazon's Product Advertising API, formerly Amazon Associates Web Service (A2S) and before that known as Amazon E-Commerce Service (ECS), is a web service and application programming interface (API) that gives application programmers access to Amazon's product catalogue data. Accessible via either the SOAP or REST protocols it enables products to be listed and/or sold through third-party websites and applications. It is a product of Amazon Services, not to be confused with Amazon Web Services
AMAZON REKOGNITION
Amazon Rekognition makes it easy to add image and video analysis to your applications using proven, highly scalable, deep learning technology that requires no machine learning expertise to use. With Amazon Rekognition, you can identify objects, people, text, scenes, and activities in images and videos, as well as detect any inappropriate content. Amazon Rekognition also provides highly accurate facial analysis and facial search capabilities that you can use to detect, analyze, and compare faces for a wide variety of user verification, people counting, and public safety use cases.
With Amazon Rekognition Custom Labels, you can identify the objects and scenes in images that are specific to your business needs. For example, you can build a model to classify specific machine parts on your assembly line or to detect unhealthy plants. Amazon Rekognition Custom Labels takes care of the heavy lifting of model development for you, so no machine learning experience is required. You simply need to supply images of objects or scenes you want to identify, and the service handles the rest.
MICROSOT WINDOWS API
The Windows API, informally WinAPI, is Microsoft's core set of application programming interfaces (APIs) available in the Microsoft Windows operating systems. The name Windows API collectively refers to several different platform implementations that are often referred to by their own names (for example, Win32 API); see the versions section. Almost all Windows programs interact with the Windows API. On the Windows NT line of operating systems, a small number (such as programs started early in the Windows startup process) use the
Developer support is available in the form of a software development kit, Microsoft Windows SDK, providing documentation and tools needed to build software based on the Windows API and associated Windows interfaces.
The Windows API (Win32) is focused mainly on the programming language C in that its exposed functions and data structures are described in that language in recent versions of its documentation. However, the API may be used by any programming language compiler or assembler able to handle the (well-defined) low-level data structures along with the prescribed calling conventions for calls and callbacks. Similarly, the internal implementation of the API's function has been developed in several languages, historically. Despite the fact that C is not an object-oriented programming language, the Windows API and Windows have both historically been described as object-oriented. There have also been many wrapper classes and extensions (from Microsoft and others) for object-oriented languages that make this object-oriented structure more explicit (Microsoft Foundation Class Library (MFC), Visual Component Library (VCL), GDI+, etc.). For instance, Windows 8 provides the Windows API and the WinRT API, which is implemented in C++ and is object-oriented by design.
Almost every new version of Microsoft Windows has introduced its own additions and changes to the Windows API. The name of the API, however, remained consistent between different Windows versions, and name changes were kept limited to major architectural and platform changes for Windows.
GOOGLE API
Google APIs are application programming interfaces (APIs) developed by Google which allow communication with Google Services and their integration to other services. Examples of these include Search, Gmail, Translate or Google Maps. Third-party apps can use these APIs to take advantage of or extend the functionality of the existing services.
The APIs provide functionality like analytics, machine learning as a service (the Prediction API) or access to user data (when permission to read the data is given). Another important example is an embedded Google map on a website, which can be achieved using the Static maps API, Places API or Google Earth API.
User registration is commonly done via Google, which allows users to securely log into third-party services with their Google account through the Google Sign-in system. This is currently available from within Android (operating system) or by using JavaScript.[8] It is popular to include a "Sign in with Google" button in Android apps, as typing login credentials manually is time-consuming due to the limited screen size. As the user is usually signed into their Google account on their mobile device, signing-in/signing-up for a new service using a Google account is usually a matter of a few button clicks. Drive apps are various web applications which work within Google Drive using the Drive API. Users can integrate these apps into their Drive from the Chrome Web Store, allowing them to work entirely in the cloud.[9] There are many apps available for collaborative document editing (Google Docs, Sheets), picture/video editing, work management, or sketching diagrams and workflows.
Custom Search allows web developers to provide a search of their own website by embedding a custom search box and using the Custom Search API. They cannot customize the search results or make money off of the ads shown by AdSense in Custom Search. App Engine are web apps that run on the Google App Engine, a platform-as-a-service (PaaS) cloud computing platform which allows web developers to run their websites in Google datacenters. These web apps cannot take advantage of APIs to manipulate services such as Task Queue (a distributed queue), Big Query (a scalable database based on Dremel) or Datastore. Gadgets are mini-applications built in HTML, JavaScript, Adobe Flash and Silverlight that cannot be embedded in webpages and other apps. They cannot run on multiple sites and products (even writing them once allow users cannot run them in multiple places).
The table shows the speech and text processing API’s comparison in the document file.
The link below shows the document file.
API.docx