Button Group
Join related buttons into one control, or split one action from its variations. Distinct actions stay apart.
Split
One action with a few ways to do it. The label runs the common case; the chevron holds the variations, like Redeploy without cache or Visit another domain. Never for unrelated actions.
Attached
Two to four buttons that act on the same thing join into one control: the log stream and its contents, or two filters on the same data. Outlined buttons share one ring at each seam.
Stepper
Previous and next always travel as a pair. Clear or Close is a different action, so it stands apart.
In Place of a Menu
When there are only a few options and people reach for them often, show them as a group instead of hiding them in a menu. The sidebar footer keeps Docs, Feedback, and Changelog one click away; the rarer items stay in the account menu.
Standalone
Different actions stay apart with a gap, however many sit side by side, and so do the buttons in every dialog and sheet footer. Rare, destructive, or copy actions go in a … menu; table rows keep one inline action at most. To choose between views, use a segmented control instead.