Quicksilver is essentially a graphical shell for the macOS operating system, allowing users to use the keyboard to rapidly perform tasks such as launching other apps, manipulating files, or sending e-mail.

Quicksilver uses a priority system based on prior usage to "learn" the user's habits, ultimately requiring only a few letters for the most commonly selected objects.

Quicksilver allows users to define "triggers," which perform a specific command (direct object/action/indirect object combination) whenever a customizable keyboard shortcut is pressed.

For instance, if a command opening the Documents folder is bound to the F7 key, this hotkey would trigger that action regardless of what application the user is currently in.

For example, plug-ins exist for sending email via Mail without opening the application or manipulating images via text commands.

[11] At the end of 2010, the new website QSApp.com was launched, with the aim of unifying and collating all of Quicksilver's fragmented builds, plugins and support groups.