Commands define actions that SilverBullet can perform. They range from simple edit commands, such as Text: Bold, but may be more elaborate such as Page: Rename.
SilverBullet ships with a lot of commands built in, but custom ones can also be defined using Space Lua and Plugs.
Available commands appear in the Command Palette but may have key bindings as well (these key bindings appear in the Command Palette and are configurable in the Configuration tab).
You can create custom commands using the ^Library/Std/APIs/Command API.