Essential knowledge in object-oriented technology

On
Objects.cz,
Ilja Kraval asks What Should You Absolutely Know About Object-Oriented Technology?
Among other things, I’d highlight his point about dividing project staff into four roles.

• Analyst
• Designer
• Programmer
• Project manager

Here is the essential knowledge those roles require.

• 1. A thorough grasp of the object-oriented approach and how to think in objects
• 2. Object modeling and UML
• 3. Basic principles for building systems in an object-oriented environment
• 4. Design patterns in OOP