2. How arrays and collections differ

• An array is a Java language feature. Collections are classes in the Java API.

• Collection classes have methods that perform operations that arrays don't provide.

• Arrays are fixed in size. Collections are variable in size.

• Arrays can store primitive types. Collections can't.

• Indexes are almost always required to process arrays. Collections are processed without using indexes. Rather, collections provide methods such as

  • get(index) // returns stored value

  • set(index, object) // updates stored value