Dear Shreekant,

SQL Server has following 3 types of backup:

1.Full backup

2.Differential backup

3.Transaction log backup

Full backup takes backup of complete data and log file upto that time.

Differential backup takes backup of all data changes since the last full backup.

Transaction log backup works in the form of a continuous chain. After full backup transaction log backups can be scheduled such that they form a continuous chain.

Probably when you say incremental you meant Differential.. 🙂

Regards

Shafat Husain