What are the different users and permission levels in SharePoint 2010 while creating a new site ?

If you are going to select use unique permissions option while creating a new site then users are required. Also you can check some SharePoint and Asp.Net Jobs.

SharePoint 2010 categorizes users of a site into three SharePoint groups . Thease are Visitors, Members, Owners.

Visitors: People or groups can only read the content of a site.

Members: They can only create and edit contents but can't create lists or manage site membership.

Owners: They have the capability for all aspect of creating and managing a site.
When users are added to a site ,they must be added to a sharepoint group or associated with at least one permission level.

SharePoint provides 5 permission levels. These are Read, Contribute, Design, Full Control, Limited.

Read: Here user can only view site content.

Contribute: The user can view,add,update and delete the content of a site.

Design: Here user can view,add,update,delete,approve and can able to customize the content of a site.

Full Control: The user can able to do every operation over the site content.

Limited: The user has permissions to do operations over some specific lists,document libraries, folders, list items .
The Visitors group has the permission level Read.
The Members group has the permission level Contribute.
The Owners group has the permission level Full Control.