Hadoop Provides big companies a mean to distribute and store huge amount of data on not only one computer but multiple! You can imagine it like you normal Window or Unix Filesystem, but only distributed! At first you might think, wow ok so what, now I have my 4K Video on 5 different Computers, what do we get from that?
Usually, only one computer supplies us with the data we want, this one computer only has 1 Network connection and limited bandwith. If you have multiple computers in different locations using different connections to the internet, their bandwith sums up and a high perfomance boost will be noticable
You can imagine it, as 1 Person having to deliver a giant rocket consisting of multiple big parts. That one person can only deliver 1 Rocket part at a time. If we use 2 Persons, we already doubled our speed ! The same principle applies to down loading and uploading
So instead of just 1 Computer supplying you with a limited Datastream, you have multiple Computers serving you Data at the same time!
IF you want to setup Hadoop on your Local machien check <THIS> out!
If you are intrested in setting up a Hadoop pseudo cluster check <THIS> out!
If you want to learn about basic java interacting with Hadoop, downloading, uploading from a Distributed File System , check <THIS> out!