Is the current method used by investment banks to value companies DCF or Multiple?

The most common methods of valuing companies are divided into two categories: absolute valuation using the discounted cash flow method, or DCF, and relative valuation using trading comps and transaction comps.

There are too many DCF techniques to write a book, and transaction comps is not applicable to most general investors due to information barriers, so I hope to provide some stock investors with some value investment methods and ideas.