Usually a combination of these reasons leads to the choice for a distributed environment. It is generally acceptable not to notify readers that the node has changed. Frequent access to the same remote nodes can be eliminated by means of replication. This feature can be implemented by means of mirroring or caching. Mirroring a well-defined part of the information is what is done most in distributed databases, while caching is more popular in operating systems and in distributed hypertexts.
Cache coherency is less critical in hypertext than it is in operating systems.
Collaborative writing requires more concurrency control features, including locking, notification, transactions and versioning. The test on Distribution and Concurrency in Hypertext is used to verify your knowledge on this subject.