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Collection is a framework that provides an architecture to store and manipulate a group of objects. The Collection interface is part of the Java Collections Framework, which provides a unified architecture for representing and manipulating collections. It includes interfaces, implementations, and algorithms to handle data manipulation tasks such as searching, sorting, insertion, deletion, etc.

The main interfaces in the Java Collections Framework include:

1. Collection - The root interface for the collection hierarchy.
2. List - An ordered collection (also known as a sequence) that can contain duplicate elements. Example implementations include ArrayList, LinkedList.
3. Set - A collection that cannot contain duplicate elements. Example implementations include HashSet, LinkedHashSet, TreeSet.
4. Queue - A collection used to hold multiple elements prior to processing. Example implementations include PriorityQueue, LinkedList (as a Queue).
5. Map - An object that maps keys to values, with no duplicate keys allowed. Example implementations include HashMap, TreeMap, LinkedHashMap.

classDiagram
    Iterable <|-- Collection
    Collection <|-- List
    Collection <|-- Set
    Collection <|-- Queue

    class Iterable {
        <<interface>>
        +iterator()
    }

    class Collection {
        <<interface>>
        +add(Object)
        +remove(Object)
        +size()
    }

    class List {
        <<interface>>
        // Ordered collection
    }

    class Set {
        <<interface>>
        // No duplicates
    }

    class Queue {
        <<interface>>
        // FIFO collection
    }

    class Deque {
        <<interface>>
        // Double-ended queue
    }

    class Map {
        <<interface>>
        // Key-value pairs
    }

    class SortedSet {
        <<interface>>
        // Ascending order
    }

    class NavigableSet {
        <<interface>>
        // Navigation methods
    }

    class SortedMap {
        <<interface>>
        // Ascending key order
    }

    class NavigableMap {
        <<interface>>
        // Navigation based on keys
    }

    List <|.. ArrayList
    List <|.. LinkedList
    List <|.. Vector
    List <|.. Stack

    Set <|.. HashSet
    Set <|.. LinkedHashSet
    Set <|.. TreeSet

    Queue <|.. PriorityQueue
    Queue <|.. LinkedList

    Deque <|-- Queue
    Deque <|.. ArrayDeque
    Deque <|.. LinkedList

    Map <|.. HashMap
    Map <|.. LinkedHashMap
    Map <|.. TreeMap

    SortedSet <|-- Set
    SortedSet <|.. TreeSet

    NavigableSet <|-- SortedSet
    NavigableSet <|.. TreeSet

    SortedMap <|-- Map
    SortedMap <|.. TreeMap

    NavigableMap <|-- SortedMap
    NavigableMap <|.. TreeMap

Iterable → is a interface if used then we can use for loop

List Interface