Web Development
[01]
Server and Client
Website software is divided into two areas, 'client side' and 'server side'.
Client side software runs on your own computer as you click buttons, fill in forms and use menus on a web page. It reacts to your actions and can do things like change an image as you move your mouse over it, make paragraphs or pictures appear and disappear as you click buttons, and even load a new page.
Server side software runs on the server that hosts your website and performs tasks like checking your user name and password against a database when you login, or retrieving the right web page when you search for something. Server side software runs online shops and processes your shopping basket and credit card payment when you buy from them.
[02]
Client Software Makes Websites Fun
Because client side software reacts to things you do it lets web developers bring web pages to life with interractive slideshows, folding or 'concertina' paragraphs (that expand to show you the bits you're interested in and hide the rest), even menus that follow you down the page as you scroll. Client side software is typically used in small pieces at a time known as 'scripts' and most of it is written in a language called Javascript, tho some websites use a Microsoft alternative known as VB Script..
At Abbeydale we use Javascript to write our client side software and frequently use it to protect email addresses on the web, to validate forms, drive multi-level menu systems....
[03]
Server Software Does the Heavy Lifting
Because it runs on the web server, server side software is relatively secure and can handle sensitive information like passwords and prices and reveal them only to authorised users. It can be trusted to handle resource bookings without giving away who else has booked you and when. Server side software can handle databases of millions, even billions of records so it can run online banking sites, search engines and 'e-government' - much of the UK tax system is now online and run by server side software.
Server side software is written in a number of programming languages including PHP, ASP, C/C++ and Java. We use the PHP language and MySQL databases to write most of our software tho we have also used C and C++ extensively in the past.
[04]
Bringing It All Together: AJAX
A comparatively recent development called AJAX (Asynchronous Javascript And XML) lets Javascript programs on your computer talk directly to software on the server to bring you highly interractive and responsive web applications based on server side databases.
