The 60-second collaboration model

Record access → Conversation or Topic → Mention or involvement → Subscription level → In-app notification → Optional delivery channel

• A Topic is a named, shareable drawing-markup layer that can span sheets and hold conversation.
• A comment is one message. It may start a conversation on a drawing, Topic, RFI, Submittal, bid, photo, or other supported record.
• A Thread is the full conversation made from the first comment and its replies. Threads is the inbox that brings your accessible conversations together.
• An internal project discussion is a Thread attached to the project itself rather than to another record. It requires a separate project-discussion permission.
• A mention calls a person into an event, but delivery still depends on access and notification settings.
• A subscription says how much activity you want from a channel, project, or individual record.
• Email, desktop, and mobile settings control where notifications are delivered. They do not decide what records you can see.