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Bandwidth
This refers to the amount of data that is transfered over the internet. If you have many visitors, or your website is very image intensive, then you will use more bandwidth than if you had fewer visitors to your site, or if your site was very simple with light pages. You pre-purchase an amount of bandwidth that you can use each month.
Content Management System
Referred to as CMS, a content management system is a web enabled interface that allows user(s) to manage their website. Administrators use a username and password to log in to an administration console, where they can perform tasks such as adding, editing or deleting content pages and navigation items, or managing site users. Tom, Dick & Harry currently supports the following content management systems: Joomla, Wordpress and MODx.
Disk space
This refers to the amount of storage space available to your website on the hosting server. If you have many site files, or you use lots of big images, then your site will take up more disk space than a smaller website.
Excess Bandwidth
This refers to any bandwidth that you need over and above your monthly allocation. This is like back-up bandwidth - there if you need it, but usually not required. If you find that you are regularly overshooting your monthly bandwidth allocation, then you probably need to consider moving up to the next package.
Static Website
This is a website that consists of static files. To make changes to a static website, you need to open the website files in a text editor and manually change the code. Usually an FTP editor is used to transfer the files back and forth between the live hosting server and the local development environment.