Metadata is commonly defined as data about data. But I would rather define it as content about content, additional content that is intended to help the user to interpret main content by adding context to it, by putting it in the context of other content. Metadata can provide answers to questions the user might have about the content, such as who created it and when or what subject it is about. Content without any metadata is more or less useless. It is hard to find it, hard to understand where it came from, hard to determine if it is accurate and up-to-date or not, and so on.
“Content that has been adequately tagged with metadata can be leveraged in usage tracking, personalization and improved searching.” (GIGA)
Metadata is a key ingredients to help users find the content they are looking for. One of the big problems with finding content on the web and in private networks is that most content is textual, written in natural language, which is hard for computers to effectively manipulate and manage. Computers cannot understand the meaning of a piece of content (the semantics), only determine the structure of it (the syntax). So, when you search for content, the search engine will look for content that contains the same words and has the same syntax as your query. But it cannot understand what the words mean. This makes searching quite inefficient.
But this is also where metadata comes into the picture. By tagging the content with words (keywords) that tell more what the content is about than most of the words within the content itself do, the search engine can look for content that contains keywords that are the same as the words you provided in the query. This increases the efficiency of search, enabling more relevant search results.
Once the right content can be easily found and retrieved, metadata can also help with many other things with the content, such as reusing it for other purposes, preserving it, making sure only the right users can access it, and so on.
In other words, metadata is the DNA of a content enterprise, vital for its growth, survival and success. The metadata has to be good, and it has to be the right metadata. Equally importantly is that there is an enterprise taxonomy that organizes all content semantically. But more about that later.