A marker is a pointer to a specific location within a buffer. Each buffer can have any number of markers associated with it. Markers are persistent; they are saved to .filename.marks, where filename is the file name. (The dot prefix makes the markers file hidden on Unix systems.) Marker saving can be disabled in the Loading and Saving pane of the Utilities>Global Options dialog box; see the section called "The Global Options Dialog Box".
Markers>Add/Remove Marker (shortcut: Control-E Control-M) adds a marker without a shortcut pointing to the current line. If a marker is already set on the current line, the marker is removed instead. If text is selected, markers are added to the first and last line of each selection.
Markers>Remove All Markers removes all markers set in the current buffer.
Markers are listed in the Markers menu; selecting a marker from this menu will move the caret to its location. A quicker way to return to a marker's location is to give it a shortcut. The following commands all prompt for a single-character shortcut when invoked. Pressing Escape instead of specifying a shortcut will cancel the operation.
Markers>Add Marker With Shortcut (shortcut: Control-T key) adds a marker with the specified shortcut. If marker with that shortcut already exists, it will remain in the buffer but lose its shortcut.
Markers>Go to Marker (shortcut: Control-Y key) moves the caret to the location of the marker with the specified shortcut.
Markers>Select to Marker (shortcut: Control-U key) creates a selection from the caret location to the marker with the specified shortcut.
Markers>Swap Caret and Marker (shortcut: Control-U key) moves the caret to the location of the marker with the specified shortcut, and reassigns the marker to point to the former caret location. Invoke this command multiple times to flip between two locations in the buffer.
The last two commands provide a way to move between markers using the keyboard even if they do not have shortcuts.
Markers>Go to Previous Marker (shortcut: Control-E Control-,) goes to the marker immediately before the caret position.
Markers>Go to Next Marker (shortcut: Control-E Control-.) goes to the marker immediately after the caret position.
Lines which contain markers are indicated in the gutter with a highlight. Moving the mouse over the highlight displays a tool tip showing the marker's shortcut, if it has one. See the section called "The Text Area and Gutter" for information about the gutter.