Sorry Jezelll, had to throw a downvote. This is not what I would consider 'plain english' :( I don't have a problem with the intent of your definition, but using words like 'operation', 'remote server', 'invoked' and 'specification' makes it hard for beginners to understand. See Mitchel Sellers answer as an example of 'plain english'. – Dhaust Jun 30 '09 at 23:53
A web service is something that a website chooses to offer to those who wish to read, update and/or delete data from your website. You might call it a "backdoor" to your data. Instead of presenting the data as part of a webpage it is provided in a pre-determined way where some of the more popular are XML and JSON. There are several ways to communicate with a webservice, some use SOAP, others have REST'ful web services, etc.
Once you decide you price range, you need to consider how long you'll need web hosting. If it's a short-term project—say, less than a month or two—you can typically receive a refund should you cancel your hosting within 60 days. Some companies offer 30-day money-back guarantees, others offer 90-day money-back guarantees. Once again, it's beneficial to do your homework.
"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
But, again, operationally it's quite strong. 24/7/365 customer support is available not only by live chat and email, but by phone. It offers free site migrations with some dedicated attention paid to making a transfer as smooth as possible. And, if you're willing to go for one of the higher-end plans, the company has put some serious attention into performance and caching.
In housing terms, VPS hosting is like renting your own apartment in a larger building. You're much more isolated than in the roommate situation mentioned above; it's still possible that a neighboring apartment could causes annoyance for you, but far less likely. In web hosting terms, Site A's traffic surge won't have nearly as much impact on Site B or Site C. As you'd expect, VPS hosting costs more than shared hosting. You'll pay roughly $20 to $60 per month.
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.
Before the Web was developed, images would primarily be downloaded manually from file servers or from binary newsgroups on Usenet, and displayed with a separate image viewer. The expansion of the Web in the 1990s brought text and images together, allowing for inline display of images without separate downloading, but still required the above expertise and methods to make the images available.