Microsoft 365

OneDrive is a person’s file library in Microsoft 365. SharePoint is the team’s site and libraries. Both use the same file engine; ownership and sharing rules differ.

A Team is a membership group with channels. A channel is a topic with its own conversation and files. A chat is a thread between people and is not a Team.

A SharePoint library is a container for files on a site. Permissions inherit from the site unless you break inheritance. Unique permissions on every folder do not scale.

Guest access is an Entra ID account for a person outside the tenant. External sharing is a link or permission on a file, library, or Team. They overlap but are not the same control.

An Exchange Online mailbox is the mail, calendar, and people data attached to an Entra ID user. Aliases and send-as are addressing rules on that mailbox, not extra mailboxes.

A shared mailbox is one inbox several people open. A distribution group is a list that fans mail out to members. A Microsoft 365 group is a membership object with a mailbox plus files and often a Team.

Microsoft Entra ID is the identity service behind a Microsoft 365 tenant. It stores users, groups, and sign-in policies so people and apps can access mail, Teams, and files.

MFA asks for a second proof at sign-in. Conditional Access is the policy engine that decides when MFA, a compliant device, or a block applies.

Microsoft Intune is the cloud service that enrols phones and PCs, then applies app, update, and protection policies from Entra ID. It does not replace identity; it enforces the device.

Admin roles in Microsoft 365 are Entra ID directory roles that limit who can change users, mail, SharePoint, billing, or the whole tenant. Most staff should hold none of them.