You can manage user roles for your site in the Admin Panel area of your site. Simply click Users in the left-hand column of your Admin area to add users and assign them different roles.
Administrators have access to all the administration features; editors can publish posts, manage their posts, and manage others’ posts; authors can publish and manage their posts; contributors can write and manage but not publish their posts; subscribers can read comments, make comments, and receive newsletters.
You must have at least one administrator, but the remaining roles are not required, and there is no limit on the number of people who can occupy each role.
If you choose to create a group site, you can assign these roles to different members as part of the group or site creation process. Roles are covered in more detail in this guide.