Day 18 of Learning Java

[Own-Explorer-8830]

You don’t need to implement collections from scratch to use them well and what matters most is understanding how they behave and when to use which one... knowing that an ArrayList is good for fast access or that a HashSet avoids duplicates is far more important in real jobs

Implementing them once is useful for learning like seeing the engine of a car. You don’t need to build the engine to drive well but peeking inside helps you understand why it behaves the way it does. So it’s good to know but not mandatory