Why re invent the easy bulb

https://www.mediafire.com/file/93novtchotu80to/pdf-30447-45162.pdf/file

Why Re-invent the Light bulb?<br/>Have you ever had a predicament with a burned gentle? Thanks to the effort of Thomas Edison we not want to invent a easy bulb. We just go to the shop or our cupboard and pull one out and screw it in