Introduction

Big Data is one of the hottest topics trending today. And it is growing day by day. The demand for Data Scientists (Big Data experts) is very high. Most people say it requires a Ph.D. degree but according to my, it is a good but not a necessary one. One who wants to enter into the field of Data Science must have knowledge about different fields.
  1. Strong Mathematics background
  2. Statistics
  3. Programming
  4. Computer knowledge using Excel etc.
Now, what actually is Big Data ….?
Many different people and companies define it differently. IBM defines it as -
“Big data is the data characterized by 3 attributes: volume, variety, and velocity.”
Oracle defines it as -
“Big data is the data characterized by 4 key attributes: volume, variety, velocity and
value.”
Google dictionary defines it as -
“extremely large data sets that may be analyzed computationally to reveal patterns, trends, and associations, especially relating to human behavior and interactions.”
But, I will define it differently.
Think 15 years back, when we were using computers. What was Data at that time? It was in bytes or kilobytes mostly. Then, we moved to desktops and data increased to Megabytes and Gigabytes. Then, the World Wide Web got introduced and data increased exponentially and reached Terabytes and Petabytes. The following image demonstrates it:
Now today, big companies like Microsoft, Google, eBay, Amazon, and Netflix all have a lot of data about users. The whole data in the world has doubled in just the last two years. Today, data is available in Exabytes and Zettabytes. The following image may clear the concept.
This is known as the Big Data that is stored in the top big databases in the world. Every company is saving its customers' data on servers for many useful purposes.
Why Big Data?
Now, the biggest question here is why companies rely on Big Data and what are its main advantages.
The answer to this question is straight forward. Companies use this data for many purposes, the main purpose being understanding the customer behavior - their liking, their understandings, etc. Moreover, it is used for predictions and more. Following is the description of some giant companies that are using the best use of Big Data.
  • Google
    Google is using Big Data for advertisements. From previous knowledge, they understand the user's likes, shopping behavior, types of ads a user clicks most often, and then they post ads on users' pages that best suit the users' behavior.
  • Amazon
    Amazon is best known for its online selling and purchasing. If someone buys some book or CD/DVD from Amazon, they save customer's data, and then from previous data, they predict the customer's interests followed by recommending products geared to their interests.
  • Netflix
    Netflix also predicts users' interests and behaviors by previous data and then they recommend movies and create interesting content as per the recorded pattern.
  • Airbnb
    Airbnb also uses Big Data. They store a large amount of customer data and then, recommend to them the perfect price.
Big.... means Big
From the above discussion, we can conclude that these companies understand customers by their previous data. So, Big means - a large amount of data is needed to perform these useful operations. The above-mentioned companies and many more in the world have turned their businesses into multi-million dollar ones by using Big Data Analytics.