Logical and physical backups are two types of methods used to backup PostgreSQL databases, each with its own advantages and use cases. Logical backups involve translating data into SQL commands that can be executed on any database cluster, making them ideal for simple backups, migration between major versions, and backing up a single database. On the other hand, physical backups involve copying actual files or file systems where database data is stored, making them more suitable for larger databases and achieving point-in-time recovery through Write Ahead Log (WAL) files and tools like WAL-G.