What is ?

Description
Objects and classes
Class-based vs prototype-based
Dynamic dispatch/message passing
Data Abstraction
Encapsulation
Composition, inheritance, and delegation
Polymorphism
Open recursion
Inheritance and behavioral subtyping
Gang of Four design patterns
Object-orientation and databases
Real-world modeling and relationships
Method and method passing
Pillars of OOPs
Compile-time polymorphism
Runtime polymorphism
loose coupling vs tight coupling
Class method vs Instance Method in objective-C
opaque type vs protocol vs associated type vs generics
What is TDD

Description
Instrument in IOS
Profiler in Android
Dependancy Injection
Dependancy Inversion
What is Hashing
What is Salt in Pasword Encryption
LIFO
FIFO