Action list is a vertical list of interactive actions or options. It's composed of items presented in a consistent, single-column format, with room for icons, descriptions, side information, and other rich visuals.
Action menu is composed of action list and overlay patterns used for quick actions and selections.
Avatar stack displays two or more avatars in an inline stack.
Branch name is a label-type component rendered as an <a> tag by default that displays the name of a branch.
Breadcrumbs display the current page or context within the site, allowing them to navigate different levels of the hierarchy.
Button is used to initiate actions on a page or form.
Button group renders a series of buttons.
Checkbox is a form control for single and multiple selections.
Checkbox group renders a set of checkboxes.
Counter label is a button with a numbered label accompanied by text.
Data table is a 2-dimensional data structure where each row is an item, and each column is a data point about the item.
Header is a navigation bar that has all of its items aligned vertically with consistent horizontal spacing.
Heading defines the hierarchical structure and importance of the content they contain.
Icons at GitHub are called Octicons, which are available in various implementations including React, Figma, Rails, and Styled System.
Icon button is used for buttons that show an icon in place of a text label.
Use the label component to add contextual metadata to a design.
Links are used to apply styles to hyperlink text.
Nav list renders a vertical list of navigation links.
Pagehead denotes the title and start of a given section.
Pagination is a horizontal set of links to navigate paginated content.
Progress bar visualizes one or more parts of a whole.
Radio button is a form control for making a single selection from a short list of options.
Select is an input for selecting a single option from a menu.
State label is used for rendering the status of an item.
Tab nav contains a set of links that let users navigate between different views in the same context.
Text input is used to set a value that is a single line of text.
The timeline component is used to display items on a vertical timeline, connected by timeline elements.
Tree view is a hierarchical list of items that may have a parent-child relationship where children can be toggled into view by expanding or collapsing their parent item.
Anchored overlay opens an overlay relative to the anchor position.
Autocomplete allows users to quickly filter through a list of options and pick one or more values for a field.
Avatar pair is composed of two avatars, one larger one and a smaller one, overlaid slightly.
Blankslate is used as placeholder to tell users why content is missing.
Box is a basic wrapper component for most layout related needs.
Circle badge visually connects logos of third-party services, eg. in the marketplace.
Clipboard copy copies element text content or input values to the clipboard.
Comment box allows users to write and preview comments.
Details is a styled component to enhance the native behaviors of the <details> element.
Dialog is a floating surface used to display transient content such as confirmation actions, selection options, and more.
Flash alert informs users of successful or pending actions.
Form control displays a labelled input and, optionally, associated validation text and/or hint text.
Use label group to add commonly used margins and other layout constraints to groups of Labels
Page header determines the top-level headings of a UI.
Popover is used to bring attention to specific user interface elements.
Radio group is used to render a short list of mutually exclusive options.
Segmented control is used to pick one choice from a linear set of closely related choices, and immediately apply that selection.
Use Spinner to show users that an action is in progress.
Stack is a layout component that creates responsive horizontal and vertical flows.
Tab panels let users switch between views in the same context.
Text input with tokens is an input for a value that is a list.
Textarea is used to set a value that is multiple lines of text.
Toggle switch is used to immediately toggle a setting on or off.
Token is a compact representation of an object, and is typically used to show a collection of related metadata.
Tooltips add additional context to interactive UI elements and appear on mouse hover or keyboard focus.
The underline nav is used to display navigation in a horizontal tabbed format.
The underline panels are used to break related content into tabbed panels.
Avatar is an image that represents a user or organization.

Action bar contains a collection of horizontally aligned buttons.