For the longest time web hosting setups were made to accommodate only one web site to be hosted. As technology has improved as well as structures, a shift has been seen in the offerings from those allowing you to purchase web hosting. The ability to include a certain number of addon domains in their packages has been added, and some allow unlimited add on domains. A wise choice is to still not host too many domains within the same account, but this is a huge money saver for those who may want to host a couple of small sites.
In simple terms, the name implies what it does in that it allows you to add on a domain to your existing hosting account. You will always host a primary domain name for your account, and your addon domain will be normally hosted within a subfolder on that account. So when you connect via ftp the first folder you see will be for maindomain.com files. You will then create a subfolder or the hosting will create the subfolder for you (typically related to the domain), like a folder named addondomain.com, will contain the files for your second domain. Now if you type maindomain.com, you will see it as its own site, and the same for addondomain.com. A website visitor will not be able to distinguish that the sites are hosted on the same hosting account, and will feel like its own site.
Almost all web hosts now promote affordable low cost web hosting solutions, and normally the mid to higher based packages will offer add on domains as an option. Note, this does vary from provider. Once you find the provider you want to go with, you then setup as many domains as they allow as addons using their procedures. You do have to remember not to delete these subfolders or your site will stop working, and it may get messy with too many subfolders for addon domains.
Happy savings when you are now able to host ten domains with one hosting account instead of only one.
