Many registrars also offer registration through reseller affiliates. An end-user registers either directly with a registrar, or indirectly through one or more layers of resellers. As of 2010, the retail cost generally ranges from a low of about $7.50 per year to about $35 per year for a simple domain registration, although registrars often drop the price far lower – sometimes even free – when ordered with other products.
If you are looking for a domain, WhoIs domain lookup can tell you if it's already owned by another entity and provide contact information for the domain name owner. WhoIs domain information can help you determine the proper contact for any domain listed in the Whois database. A WhoIs lookup identifies the administrator contact information, billing contact and the technical contact for each domain name listing or IP in the WhoIs database. A WhoIs IP search can also help you potentially determine the source of spam and other details related to a website.
Web services allow different organizations or applications from multiple sources to communicate without the need to share sensitive data or IT infrastructure. All information is instead shared through a programmatic interface across a network. This interface can then be added to a GUI, like a web page, to deliver specific functionality to users. Due to this, web services are not specific to one programming language or operating system and do not require the use of browsers or HTML.
A web service is a collection of open protocols and standards used for exchanging data between applications or systems. Software applications written in various programming languages and running on various platforms can use web services to exchange data over computer networks like the Internet in a manner similar to inter-process communication on a single computer. This interoperability (e.g., between Java and Python, or Windows and Linux applications) is due to the use of open standards (XML, SOAP, HTTP).

The term "Web service" describes a standardized way of integrating Web-based applications using the XML, SOAP, WSDL and UDDI open standards over an Internet Protocol backbone. XML is the data format used to contain the data and provide metadata around it, SOAP is used to transfer the data, WSDL is used for describing the services available and UDDI lists what services are available.

"All the standard Web Services works using following components:" ... the problem with this answer is that it suggests that web services do or must operate within the SOAP/WSDL mechanism. This is inaccurate. Representational State Transfer (REST) is another very popular paradigm for implementing web services. Some major websites have deprecated their SOAP services in favor of REST web services. – scottb Jul 7 '15 at 15:50