What is Price-to-book ratio? How Useful is this ratio?

MARKET RATIO:Price-to-book ratio

One of the business ratio analysis which we often come across is the Price-to-book ratio.

Append below in summary what is this market ratio is all about:-

Ratio Purpose Formula Price-to-book ratio (P/B ratio) Measures the value that the stock market places on a company relative to its book value. Also [...]