Every builder needs tools and that includes those who build websites.
When Cavespider started creating websites in 1994, not far off the birth of the World Wide Web, there weren't many tools. We learnt to build websites using flint axes, ok, not quite. Now we have a large range available to us and we have the experience and knowledge to use them to best advantage.
We would probably create your website using a CMS package, probably Joomla, but we can work with Wordpress, Drupal or Concrete5 if appropriate. A CMS or content managed system allows the site to be managed by someone not expereinced in the technology. They can log in and add content, pictures, run blogs whatever they wish. Our job is to build a website that will work well with whatever content is added.
Just as an example we use technologies such as jQuery, Mootools, Warp, Ajax and a number more.
Now the statistics show that a majority of those that will be visiting your website will be doing so using a smart phone or tablet it is essential that the website we create will look good and function well regardless of what it is be viewed on. The layout and functionality has to adapt to the device being used.
Nothing worse than trying to use a website that does work or look right. Testing is absolutely essential. Our websites have to work well on any number of different browsers and devices and we have to be sure we have checked and rechecked.