Brief History of Computers – 1

Computer is nothing but a calculating machine. So it can be argued that it is just a calculator on steroids. The first calculator or adding machine to be produced in any quantity and actually used was designed and built by the French mathematician and philosopher Blaise Pascal. It could only do addition and subtraction, with numbers being entered by manipulating its dials.

In 1671 the German mathematician-philosopher Gottfried Leibniz designed a calculating machine which expanded on Pascal’s ideas and did multiplication by repeated addition and shifting. Leibniz was a strong advocate of the binary number system. Binary numbers are ideal for machines because they require only two digits, which can easily be represented by the on and off states of a switch.

Englishman, Charles Babbage, invented in the 1830’s a “Difference Engine” made out of brass and pewter (metal alloy) rods and gears, and also designed a further device which he called an “Analytical Engine”. His design contained the five key characteristics of modern computers:-

  1. An input device
  2. Storage for numbers waiting to be processed
  3. A processor or number calculator
  4. A unit to control the task and the sequence of its calculations
  5. An output device

Ada Lovelace was an associate of Babbage. She has become known as the first computer programmer.

Let’s jump few years and skip the great Alan Turing now who was an English mathematician, computer scientist, logician, cryptanalyst, philosopher, and theoretical biologist. Turing was highly influential in the development of theoretical computer science, providing a formalisation of the concepts of algorithm and computation with the Turing machine, which can be considered a model of a general-purpose computer. The “Nobel prize in Computing” – Turing Award is named after him 🙂 We’ll cover Turing in great detail some other day.

Inspired by Babbage’s analytical engine, IBM and Dr. Aiken of Harvard designed Harvard Mark 1. It was made of switches, relays, rotating shafts, and clutches. It was 8 feet high and 55 feet long. It was the first operating machine that could execute long computations automatically. It weighed ~4284 Kilograms. Successor of Mark 1 was Mark 3 which used mostly electronic components such as vacuum tubes and crystal diodes—but also included mechanical components such as rotating magnetic drums for storage.

This was very very short history of computers. We continue with one of the most important innovations in the technology: transistor.


Hadoop 2.6.0 Multi-Node cluster setup

I have assumed that is my Master Node and and are my slaves.Now ultimately we need to assign following roles. NameNode, DataNode DataNode DataNode

First Master node :

$ mkdir -p hdfs-data
$ mkdir -p hdfs-site
$ cd etc/hadoop
$ sudo gedit hdfs-site.xml

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Hadoop 2.6.0 Single Node Setup (pseudo-distributed mode)

Hadoop is one of the most popular tool or framework for Big Data today. Usually people say that setting up Hadoop is difficult but it isn’t so. So first we need to check whether java is there or not.

$ java -version

It should show something like : java version “1.6.0_65” Java(TM) SE Runtime Environment (build 1.6.0_65-b14-466.1-11M4716) Java HotSpot(TM) 64-Bit Server VM (build 20.65-b04-466.1, mixed mode) If you don’t see something like this then you need to install java first.

$ sudo apt-get install default-jre
$ sudo apt-get install openjdk-7-jdk
$ sudo apt-get install openssh-server
$ sudo apt-get install rsync

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Impact of Microsoft in my life!

IMG_4483Microsoft Technologies always facinating for me. And the major reasons are they are affordable, available to eveyone and this is from where I started my computer journey(Windows 95).

<– My first windows Laptop. Still supports windows 8.1 without any hassle. ❤ That’s the power of windows.

Four ways Microsoft Technologies are helping me:

1. Development:

‘Availble to everyone’ is too much advantaneous for developers like us. Imagine technology available to most of every person who uses computer and plus easiest available way to develop an app.

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castAR : Here is the Future of bridging the physical world with the virtual worlds …

castAR: the most versatile AR & VR system

What is castAR?

castAR is a projected augmented reality system that displays holographic-like 3D projections right in front of you. Star Wars: Episode IV – A New Hope sparked our imaginations of what might be possible in the future by showing R2-D2 and Chewbacca playing a holographic 3D chess-style game. It has taken nearly 35 years since the film was released for this technological dream Continue reading