You can create dashboards for your own use only, or you can share any dashboard you create by selecting the Share with all users check box on the Edit Dashboard page.

When dashboards are shared, console users in Administrator or PowerUser groups, or in custom groups with Manage Shared Dashboards permission, can modify or delete the dashboard.

Keep in mind that other users might rely on a dashboard that you share. If you turn off sharing for a dashboard or delete the dashboard, other users will lose access.