The User-interface of the web is about the beautiful and attractive interface you see when you visit a website, such as the text, the colours, images, animations, forms and every other thing you can see web browsing a website, try and see it this way, the user-interface of the website is about the client-side area and it is the main business of the web designer, graphic designer and other creative people out there.
Now you may be thinking, am I going to go through all this and the answer is yes! If you wish, because this book is designed to guide you through the building of a web solution from start to finish, although you can skip this part and let your designers handle this.
You must have read in the introduction when we mentioning html, and you might not be very comfortable with this term if you are new to web, so we discuss more about HTML here.
HTML tag can be written into file or page with .htm or .html file extension e.g. Index.htm or index.html
HTML keep improving from the older versions to XHTML to HTML4 and now HTML5 in future we may see more versions coming up, but regardless of which version;your knowledge in an older version can be very useful in newer versions, this is called backward compatibility in programming. the difference between any version two, tags are not much.
The calculate.js can now be called or refer to in HTML file.
CSS (Cascading Style Sheet):