Under IFRS, there is no distinction between business combinations. Under US GAAP, there are four types: merger, acquisition, consolidation, and variable interest entity.
The acquisition method is used for business combinations.
The major points related to the acquisition method are listed below:
Partial goodwill = fair value of the acquisition – acquirer’s share of the fair of all acquiree’s assets and liabilities
Full goodwill = fair value of the entity as a whole – the fair value of all acquiree’s assets and liabilities