Fiscal years affect reports and quotas only.

When creating a holiday, you must associate it with business hours.

Global Quick Actions can be launched from the record and is automatically associated with it.

Rollup summary fields can work with master-detail and lookup relationships.

Lookup Relationships DO NOT inherit the sharing and security from another object.

Many-to-many relationships must have junction objects.

Master-detail relationships are tight relationships; detail records inherit the security of the master records; rollup summary fields are available; maximum of two master detail relationships per object.

Field Accessibility is used to control the ability of users to view or edit specific fields on  a record and Field Level Security is used to control the ability of users to view, edit, or create fields on a record.

Users can create custom Salesforce mobile app pages using Lightning App Builder. 

Password policies are available at the Profile and Record Levels