Oracle Creating ER Diagrams and Data Dictionaries

I am new to Oracle Databases and would like to develop a data dictionary and ER Diagrams for our existing databases. Do you have any tips, scripts, tools for doing so?

Oracle's Data Modeller can reverse-engineer from an existing database. They were charging for it at one time, but it is now free to use.

StackExchange Database Administrators Q#973, answer score: 21