Dashboards show data from source reports as visual components that provide a snapshot of key metrics and performance indicators. Dashboards need to be refreshed manually or scheduled to run on a regular basis to reflect the most recent data from the reports. The running user of a dashboard determines whose security settings are applied when the dashboard is run. If the running user is different from the viewer of the dashboard, they may see different data based on their permissions and sharing settings. Reference: https://trailhead.salesforce.com/en/content/learn/modules/lex_implementation_dashboards_and_reports/dashboards