Invention is the activity of investigating and finding a new method of achieving something, or a new device for use by people, or a new principle or concept or law that governs some physical quantities.

An invention introduces us to a new thing.  A Discovery finds something which is already there, but we have not known about it.

Great scientists like Newtons, Edison, Chandra Shekhar,  JC Bose, CV Raman, Eintstein, Archmedis, Pascal, Bernouli, Arya Bhatta, Curie, B Gates, Thomson are all great inventors. 
The invention of semiconductor transistor device by Bardeen and Brattain and William Schockley has lead to the most sophisticated computers, laptops, cell phones, calculators etc.  Every electronically controlled device makes use of their inventions.

To be an inventor one needs to be creative, objective, have analytical capacity, mathematically good, ability to correct own faults and to work alone.  Often inventors take the challenge in front of them to find solutions.

The inventors dedicated their lives to their field and to the good of mankind. Many of them sacrificed their personal life and made our life on Earth today comfortable.
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