In Sharepoint by defualt 7 permission levels
1. Full Control
3. Manage Hierarchy
6. Restricted Read
7. View Only
But its not have Add, Edit and View permission in single Level. [Contribute having Delete also]
For this we create a Custom Permission Level.
How to create custom Permission Level in MOSS 2007, follow below steps
1. Go to Site Actions
2. Select Site Settings –> Modify All Site Settings
3. It will open a new page called settings.aspx.
4. Click Advanced Permissions under Users and Permissions.
5. It will opens user.aspx.
6. Click Settings –> Permission Levels
7. It will opens a Permission Level Page
8. Click Add a Permission Level
9. It will open addrole.aspx
10. In this page u create a Custom Permission Level. Screen Shot