LabKey Server has a group & role-based security model. This means that each user of the system belongs to one or more security groups, and each group has a specific set of permissions (aka "roles") in relation to projects and folders on the system. When you are considering how to secure your LabKey site or project, you need to think about which users belong to which groups, and which groups have access to which projects and folders.
The topics in this section describe the LabKey security architecture. You may not need to understand every aspect of LabKey security in order to use it; in general the default security settings are adequate for many needs. However, it's helpful to be familiar with the security architecture so that you understand how users are added, how groups are populated, and how permissions are assigned to groups.