Customizing Permissions
Defining permissions in SharePoint can be done at the site level. Permissions can also be customized for a list, a library, a list item, or a specific document. Defining site access requires you to consider which site members require what level of access to the contents. For example, suppose that a stakeholder already has the contribute permission for the entire site, but you want to limit her access to the document library to read-only. You can do this by updating the list permission of the document library. To update this permission for the library or for a list, you:
Access the appropriate document library.
In the Library Tools, Library ribbon, click the Library Settings button. This will open the Document Library Settings page (see Figure 4-8).

Figure 4-8. Document Library Settings page
In the “Permissions and Management” section, click “Permissions for this document library”.
If the document library inherits permission from the parent, you have to stop inheriting permissions to customize permissions. Click on the Stop Inheriting Permissions button.
Enable the checkbox of each SharePoint group or site member that you wish to assign to this document library (Figure 4-9).

Figure 4-9. Document library permissions
Click on the Edit User Permissions button on the Permission ...