what are the basic differences between Book building and fixed price issue

The initial public offering can be done through either the fixed price or book building method.

There is a difference between shares offered by book building and shares offered by a normal public issue-

 

Features	Fixed price process	Book building process
Pricing	The price at which securities are offered/allotted will be known to the investor in advance.	The price at which securities are offered/allotted to investors is not known in advance. It is only possible to estimate the price range.
Demand	Only after the issue is closed, can the demand for the securities be known.	As the book is being built, the demand for securities can be determined every day.
Payment	If payment is made at the time subscription, refunds will be given after allocation.	Only after allotment can payment be made