Difference between varchar and nvarchar in SQL server

1. Character Data Type

•        varchar - Non-Unicode Data
•        nvarchar - Unicode Data

2. Character Size

•          varchar - 1 byte
•          nvarchar - 2 bytes

3.  Maximum Length

•          varchar - 8,000 bytes
•          nvarchar - 4,000 bytes

4.  Storage Size

•          varchar - Actual Length (in bytes)
•          nvarchar - 2 times Actual Length (in bytes)