Properly constructed web pages are built using up to three different languages.
The first requirement of a web page is to define the content of the web page. This is done using a markup language that defines what each of the component parts of the content are. The language that is normally used to markup the content is HTML although XHTML can also be used if you do not require the pages to work in Internet Explorer.
The HTML defines what the content is. When written properly no attempt is made to define how that content is supposed to look. After all the content will need to look different depending on what device is being used to access it. Mobile devices generally have smaller screens than computers. Printed copies of the content will have a fixed width and may not require all the navigation be included. For people listening to the page it will be how the page is read rather than how it looks that needs to be defined.
The appearance of a web page is defined using CSS which has the ability to specify which media the specific commands are to apply to so as to be able to have the content formatted appropriately for whatever device the page is being accessed with.
Using just these two languages you can create static web pages that will be accessible regardless of which device is used to access the page. These static pages can interact with your visitor through the use of forms. Once a form is filled out and submitted a request is sent back to the server where anew static web page is constructed and eventually downloaded into the browser.
The big disadavantage of web pages like this is that the only way that your visitor has of interacting with the page is by filling out the form and waiting for a new page to load.