Firstly, it should be understood that most web development houses will specialise in a specific programming language. The choice of the programming language is important as it should be in common usage, an up to date version should be employed and it needs to be well supported by the developers.
For example Spinoff Digital uses .aspx also known as .NET (along with supporting technologies and methodologies) which is a widely used Microsoft language which Microsoft fully supports.
The programmers use the language to write the code which is attached to a web design (the graphics) that displays the graphics correctly for various devices and provides the commands to enable the operation of the website or web application.
To see how graphics behave open a website on your desktop PC and then open the same site on your phone. Because of the difference in screen sizes the site will display differently on the various devices. The code recognises the size of the device the site is being opened on and displays the correct version to suite.
The operation of the site relates to what happens when a command is given by the user. For example the user may click on a menu item such as ‘Our services’ this will open the our services page. There needs to be code behind the Our Services menu to make this happen.
Every graphic, page layout and function of a website has coding behind it. You can actually see the coding. Open any website and right click on a white space area of the site. A popup will display with an option called view page source. Left click on this and you will see the source code of the site. This is what a programmer writes.
Like so many things websites look simple on the surface. Most of us believe a website is a few photos and some text so how hard can coding one be. Perhaps it is not all that hard but it is important it is done well and it is time consuming to complete to a high standard.