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what are the main language or platform used for webdesign?
Scripting language, HTML.
Programming + Scripting + Styling = Good Website.
The man above me has said it there are also CMS you can use like wordpress, joomla etc.
yeah and ruby
Just to be clear: HTML and CSS are not programming languages. They are markup languages: the mark up content to provide it with special attributes, such as position, size, meaning and context.
Each of these server-side languages have their place and purpose, with most overlapping widely but not completely. In order to answer the question of which is the best, you first need to answer the rebuttal: for what? The needs of the project will determine the toolset you will have to employ.
For example, if you are working at a company with many Microsoft technologies (Windows server, MSSQL server, MS Dynamics, etc.) and you need to integrate them in any way, ASP.NET is the tool you will need. If you are working on a greenfield site with no such requirements or the company is heavy with non-Microsoft tech, another option would probably be superior.
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