Timeline: The Timeline control (formerly the Social Pane) is the dedicated component in Dynamics 365 Unified Interface designed to provide a chronological view of posts (including system auto-posts), notes, and activities related to a record or in a dashboard stream.

Lists: To display a specific set of records, such as a view of Activities (e.g., "My Activities" or "Open Activities"), you use a List (or Grid) component. This component renders the rows and columns of the selected Entity View on the dashboard.

Microsoft Learn - Timeline: "The timeline control provides an easy and immersive experience to view information related to an entity, such as activities, notes, and posts." (Ref: Add and configure the timeline control in Power Apps)

Microsoft Learn - Dashboards: "Dashboards are collections of charts and lists... A list displays a view of records." (Ref: Create or edit dashboards)

Dynamics 365 Community: Confirms that standard dashboard components include Charts, Lists, IFrames, and Web Resources, with Lists being the method to display entity records like activities.