A data structure is a way to organize data in a computer so that it can be used efficiently.

Algorithms are instructions for manipulating data. The most commonly used data structures are arrays, stacks (also known as queues), lists, and trees. We’re going to talk about all of these in this article. 

The goal of this article is to provide an overview of data structures. It will cover the most popular kinds of data structures.

WHAT ARE DATA STRUCTURES?

A data structure is a representation of information as a set of elements. These elements can be properties of the object being represented (particular values or references to it), or they can be function objects that take part in some operations on the object.

TYPES OF DATA STRUCTURES

There are 8 commonly used data structures:

1. Arrays
2. Linked Lists
3. Stacks
4. Queues
5. Hash Tables
6. Trees
7. Heaps
8. Graphs

ARRAY

Arrays are a linear data structure that stores a fixed number of similar elements. Arrays can store both primitive data types and objects but must be of the same type. This is one of the most common data structures in Java.

LINKED-LIST

SINGLY LINKED-LIST: In a singly linked list, the node has data and a pointer to the next node. It has no pointer to the previous node. The next node points to zero so you can iterate over the linked list with this condition.

DOUBLY LINKED-LIST: In the doubly linked list, Node has data and pointers to the next node and the previous node. You can iterate through the linked list either forward or backward as it has pointers to the previous node and the next node. This is one of the most common data structures in Java.

STACK

The stack is an abstract data type that describes the last-in-first-out behavior (LIFO).

QUEUE

A queue is a linear structure that follows a specific order in which operations are performed. The order is First In, First Out (FIFO).

HASH TABLES

Hashing is a technique or process of mapping keys and values ​​in the hash table through the use of a hash function. This is for faster access to elements. The efficiency of the mapping depends on the efficiency of the hash function used.

TREES

A tree is a nonlinear data structure, as compared to arrays, linked lists, stacks, and queues which might be linear data structures. A tree may be empty without nodes or a tree is a structure consisting of one node known as the root and zero or one or extra subtrees.

HEAPS

Heap is a special tree-like data structure in which the tree is a complete binary tree.

MAX-HEAP: In a Max-Heap, the key in the root node must be larger than the keys in all of its children. The same property must be recursively true for all subtrees in this binary tree.

MIN-HEAP: In a Min-Heap, the key present in the root node must be minimal among the keys present in all of its children. The same property must be recursively true for all subtrees in this binary tree.

GRAPHS

A graph is a nonlinear data structure made up of nodes and edges. Nodes are sometimes called vertices, and edges are lines or arcs that connect any two nodes on the graph.

I hope this helps. The goal of this article was to provide an overview of data structures.

While there is a lot of depth to data structures and algorithms, it's easier to understand the material if you break it into manageable chunks.