ผ่านไปเจอเว็บ http://www.webapi.org/ ซึ่งเป็นเว็บที่รวบรวม web api ไม่ได้จะแนะนำเว็บที่รวบรวม services ต่างๆเหล่านี้แต่อย่างใด แต่จะแนะนำว่าเว็บนี้อธิบาย WebAPI ได้ดี

W3C Web API
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The W3C Web API Working Group is chartered to develop standard APIs for client-side Web Application development. This work will include both documenting existing APIs such as XMLHttpRequest and developing new APIs in order to enable richer Web Applications.


XMLHttpRequest
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This specification defines the XMLHttpRequest object, an API that provides additional HTTP client functionality for transferring data between a client and a server.


Windows Object
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This specification defines the Window object, which provides the global namespace for web scripting languages, access to other documents in a compound document by reference, navigation to other locations, and timers. The Window object is a long-standing de facto standard for HTML user agents. However, it should not be assumed based on this or the name "Window" that it is limited to HTML or to visual user agents.


http://www.webapi.org/webapi-glossary/
QUOTE
HTTP - the method used to transfer or convey information on the World Wide Web. The original purpose was to provide a way to publish and receive HTML pages.

JavaScript - name of Netscape's implementation of ECMAScript, a scripting programming language based on the concept of prototypes. The language is best known for its use in websites, but is also used to enable scripting access to objects embedded in other applications.

XML -  a W3C-recommended general-purpose markup language for creating special-purpose markup languages, capable of describing many different kinds of data. It is a simplified subset of Standard Generalized Markup Language (SGML). Its primary purpose is to facilitate the sharing of data across different systems, particularly systems connected via the Internet.

SOAP - a protocol for exchanging XML-based messages over a computer network, normally using HTTP. SOAP forms the foundation layer of the web services stack, providing a basic messaging framework that more abstract layers can build on. SOAP facilitates the Service-Oriented architectural pattern.
There are several different types of messaging patterns in SOAP, but by far the most common is the Remote Procedure Call (RPC) pattern, where one network node (the client) sends a request message to another node (the server), and the server immediately sends a response message to the client.

RPC - A remote procedure call (RPC) is a protocol that allows a computer program running on one host to cause code to be executed on another host without the programmer needing to explicitly code for this. When the code in question is written using object-oriented principles, RPC is sometimes referred to as remote invocation or remote method invocation.

REST - Representational State Transfer (REST) is a software architectural style for distributed hypermedia systems like the world wide web. The term originated in a 2000 doctoral dissertation about the web written by Roy Fielding, one of the principal authors of the HTTP protocol specification, and has quickly passed into widespread use in the networking community.

WSDL - Web Services Description Language (WSDL) is an XML format published for describing Web services. WSDL describes the public interface to the web service. This is an XML-based service description on how to communicate using the web service; namely, the protocol bindings and message formats required to interact with the web services listed in its directory. The supported operations and messages are described abstractly, and then bound to a concrete network protocol and message format.

AJAX - Asynchronous JavaScript And XML, or its acronym Ajax, is a Web development technique for creating interactive web applications. The intent is to make web pages feel more responsive by exchanging small amounts of data with the server behind the scenes, so that the entire Web page does not have to be reloaded each time the user makes a change.

JSON - stands for "JavaScript Object Notation", is a lightweight computer data interchange format. JSON is a subset of the object literal notation of JavaScript but its use does not require JavaScript.

SOA - Service-Oriented Architecture (SOA) expresses a perspective of software architecture that defines the use of services to support the requirements of software users. In a SOA environment, nodes on a network[1] make resources available to other participants in the network as independent services that the participants access in a standardized way. Most definitions of SOA identify the use of Web services (i.e. using SOAP or REST) in its implementation. However, one can implement SOA using any service-based technology. The OASIS SOA Reference Model Technical Committee is working on defining SOA independently of any specific technologies.

Web 2.0 - is a term popularized by O'Reilly Media and MediaLive International as the name for a series of web development conferences that started in October 2004. It has since come to refer to what some people describe as a second phase of architecture and application development for the World Wide Web. Web 2.0 applications often use a combination of techniques devised in the late 1990s, including public web service APIs (dating from 1998), Ajax (1998), and web syndication (1997). They often allow for mass publishing (web-based social software). The term may include blogs and wikis. To some extent Web 2.0 has become a buzzword, incorporating whatever is newly popular on the Web (such as tags and podcasts). A consensus on its exact meaning has not yet been reached.


นอกจาก RPC/SOAP WebSerivce แล้ว การติดผ่านรูปแบบ REST และ JSON ก็เริ่มนิยมขึ้นตามลำดับ อะไรๆ ก็ Ajax จริงๆ