Why almost company list on stock exchange had register in state of delaware?

I'm just curious. Why almost company list on stock exchange had register in state of delaware?

 

The tax laws are such that businesses that incorporate in the state of Delaware but that conduct ALL their business outside of the state pay no corporate taxes other than to the state in which they may operate depending on the state. I am not a laywer nor an accountant; this information is provided with absolutely no warranty. ;-)