What are Tags?
Tags are simple pieces of data (usually no more than 1-3 words) that describe the item tagged. Tags provide information about the item as well as make it easier to see related items (that have the same tag).
Why Use Tags
My first objection to tags was that I didn't understand the difference between tags and categories. After all, what do you need a tag for if you have your tagged item in a category?
But tags are different from categories. I first started understanding this when I was searching for a piece of paper in my file cabinet. I was looking for the race card for my horse Rambler. I knew that I had this document, and I assumed it would be easy to find. I went to my file cabinet and looked up "R" for Rambler. While there was a folder for him there, the race card wasn't in it. I checked to see if I had a "race" folder (I didn't) so then I looked under "P" for pets. Nothing. I then looked under "H" for horse. Nothing. I eventually found it under "G" for "Grey Rambler" which was his racing name.
If the racing card had been on my computer, I could have given it tags corresponding to all those things I looked up: Rambler, race, pets, horse, etc. Then, the next time I needed to find that card, I could look it up under any of those things and found it on the first try.
File cabinets require that you categorize your files - using a one category per file system. Tags take advantage of computers and don't force you to remember exactly what you were thinking about when you first identified the item.
Tags are Different from Meta Keywords
Tags are not keywords. Well, in a way they are, but they aren't the same as keywords written in a <meta/> tag. This is because tags are exposed to the reader - they are visible and often can be manipulated by the reader. While meta tags are written only by the author of the document and can't be modified.
One benefit of tags on Web pages is that readers can often provide additional tags that the author might not have thought of. Just like you might think of different things every time you try to look up an item in your filing system, your customers might think of different ways to get to the same thing. Robust tagging systems let them tag the documents themselves, so that the tagging becomes more personalized to everyone who uses it.
When to Use Tags
Tags can be used on any digital object. In other words, any information that can be stored or referenced on a computer can be tagged. I have used tagging:
- digital photos - many photo management programs offer tag support.
- address books - I added an additional field for my tags. Then whenever I want to send a message to my entire family, I just search on the "family" tag.
- Web pages and blogs - many blogs use this, and About is testing tags on one site.
- taxonomies - many sites use their tags as navigation, in things like tag clouds
- social media and folksonomies - by allowing other people to tag your site with their own tags, you find out what they are thinking of your pages. This is already being done on sites like Technorati.
How to Use Tags
The easiest way to use tags on a Web site is to use software that supports it. There are many blog tools that support tags. And some CMS software are incorporating tags into their systems. Manually building tags can be done, but it would take a lot of work.

