The permissions you have on a SharePoint Server site determine whether you can access the site and what you can do with the content on it. You can have different permissions for different sites and subsites. You can even have different permissions for different content on the same site.
The content and the menu options that you see on a site vary according to the permissions that are assigned to you. A site owner usually grants you permissions to a site by adding you to a SharePoint group, such as Visitors. The group has a permission level that you receive by being a member of the group.
What permission level do I have on a site?
You can have the following experiences when you access a SharePoint site according to your permission level.
Note: The following assumes the default SharePoint groups and permission levels for a site. Your experience might vary according to how the site owner assigned permissions on your site.
You have the Read permission level
If you can view the site but not make changes to the site or to the content on it, you belong to the Site visitors group, which has the Read permission level. For example, if you can view a site but can't edit a document on the site, you have the Read permission level.
You have the Contribute permission level
If you can view the site and change the content on the site, but not make changes to the site, you belong to Site members group which has the Contribute permission level.
You have the Full Control permission level
If you can change the content and the settings on the site, you belong to the Site owners group which has the Full Control permission level. One of the common tasks that a site owner performs is managing permissions.
You don't have permission to access the site
If you receive the Error: Access Denied message when you attempt to access a site, you don't have the permissions necessary to view the site. Select Request access to ask the site owner to grant you the necessary permissions.
Note: The ability to request access is an optional feature of a SharePoint site. If the feature is enabled, you can request access to a site.
Managing permissions on a site
As a member of the Site owners group, you determine the level of access to your site. You can grant users access to the whole site, or to specific information on the site, such as a list or even a single file. Assigning permission levels to a specific item can help you to protect sensitive content, such as a contract or budget information, without restricting access to the rest of the site.
SharePoint groups and permission levels help you to efficiently manage access to sites. You add users to SharePoint groups and assign permission levels to your site and to its contents. By default, permissions on lists, libraries, folders within lists and libraries, items, and documents are inherited from their parent site. However, you can assign unique permissions to items at a lower level, such as subsites, libraries, or even files.
SharePoint groups
Each site comes with a default set of SharePoint groups, such as Site owners. The name of the SharePoint group matches the name of the site. For example, if the name of the site is Marketing, a group will be called Marketing Owners. You can add people to these groups, so that you can later grant access to the group instead of having to grant access to each individual user. You can also create SharePoint groups to provide custom levels of access. You might want to provide more liberal or restrictive access to a specific group than you would to the default members of your site. For example, if you have a group of marketing managers that often gives confidential presentations, you might want to create a Marketing Managers group that can share information that's restricted from all other users of the site.
Permission levels
Each permission level has a set of permissions associated with it, based on the intended roles and tasks for that level. For example, the Site members group has the Contribute permission level by default. As a site owner, you choose which permissions are associated with each permission level (except for Limited control and Full control, which cannot be customized) or add new permission levels to combine different sets of permissions. Some sites have additional groups and permission levels that are tailored to the purpose of the site, such as publishing or records management sites.
