What are different types of backup?

MGDecodes explains complex technical concepts in simplest ways. Video explains different types of backups?
Full backup
Differential backup
Incremental backup
Synthetic full backup
Reverse incremental backup
Designing best backup strategy
Rule 3-2-1 Backup

[@user-nc3sh1si7r]

very informative. Thanks

[@sheffin007]

Excellent

[@shabnamhussain9361]

Why don't we use hdfs instead of this backups?