Documentum Overview
Documentum is "Document Management" software, which means that it provides a vault in which to store your documents. Rather than keeping their important files on a fileserver, companies put them in Document Management systems.
Documentum is like a normal filesystem (hard drive) on steroids. Instead of storing your files on your own hard disk, you store them inside the Documentum system. This allows people to access your files if they need to and allows you to access their files. It's kind of like a network file server, but much fancier.
Features
Security
Documentum provides better security than a filesystem. With a file system, if someone has access to your hard drive, they can pretty much read, edit, and even delete any file on the hard drive. With Documentum, you can prevent any individual user (or group of users) from seeing the file. In fact you can give Joe access to read the file but not change it while Bob can change it but not delete it, while Fred can't even see that it exists.
Version Control
In Documentum, each time you make a change to a file, it gets saved as a new version of the file, and you can go back in time and access any old versions.
For example, imagine that you are writing a memo and it needs to be reviewed by your boss. You give it to your boss who has lots of comments and requests some changes to it. You make these changes and then give him the modified file. He looks it over and decides he likes the first version better. If you were using Microsoft word, every time you press the save button, it would overwrite the existing file on your hard drive. In order to keep the first version intact, you would have to click Save As... from the menu bar and rename the file. After a few times of this, you have 5 files on your hard drive called memo.doc, memo2.doc, memo3.doc, etc. and you can't remember which is which.
If you were using Documentum, when you want to edit a file, you "check it out" and this will prevent anyone else from editing the file while you are editing it. When you make a change, you check it back in each time and Documentum would automatically keep track of the different versions. To you, it looks like you just have one file called memo.doc, but at any time you could bring up a list of all the previous versions of the file, who modified them, and when they were modified. Plus, each time you check a file in, you can give a little description of what you did to it so that when you look at the version history, you can tell the difference between the different versions.
Search Engine
You can search Documentum like you search the web by looking for a certain word or phrase in every file. But Documentum is even better than that. You can assign attributes (also called meta-data or properties) to the document. For example, you can specify a document's author, title, subject, and any number of keywords to describe it. You can even make up special attributes - if the document is a report, you can put in the report number or if the document is a letter, you could enter the date the letter was written. Then if someone is looking for the file and they know the report number or the date the letter was sent, they can bring it right up. Of course, you can do wild card searches and date range searches (for example, give me all the letters written last month that have the word computer in the subject).
Workflow
You can route documents around for approval inside the Documentum system. Each user has his own inbox that shows all the files that he needs to look at. You can approve the file or reject it, and you can have a whole approval process where it goes to your boss first and then to his boss, etc. It's kind of like email, but it's more automated and it keeps track of everybody's comments and who approved it when.
Event Notification
Let's say that there's a file in Documentum that someone else wrote but that you look at from time to time - a price list for your company's products, for example. Every now and then, some guy form the marketing group will change the prices in this price list, and you need to know about it. You can actually tell Documentum to send you an email whenever the document is modified. Rather than checking the file periodically to see if it has changed, you would only read it when you get an email that tells you that it has changed.
The flip side of this is that the marketing guy could tell Documentum that he wants an email anytime someone reads the document. This way he can get a feel for who is using it.
