Requires sanity checking; the section on Internal Edit mode is wrong in a few places. It seems the description of Audition Mode is incorrect with respect to scrubbing; it seems to work but not in any predictable manner.

Editor toolbar's tools, aka toolbox
Editor toolbar's tools, AKA toolbox.

Global Edit mode

Ardour has a global Edit Mode selector at the left side of the Editing toolbar, which affects how regions are moved or copied:

Slide Regions move freely. Ardour creates overlaps when necessary.
Ripple Editing affects the regions to the "right" of the edit (see below).
Lock No region motion is permitted (except for "nudge").

Ripple Edit mode provides the following:

If Snap To Grid is enabled, then regions can only move so that they align with locations determined by the current snap settings (beats, or seconds, or other region boundaries, etc). See Snap To the Grid for details.

The Smart mode toggle switch

The Smart Mode toggle button (shortcut: y) to the left of the mouse mode buttons modifies the behavior of Grab Mode: when enabled, the mouse behaves as if it is in Range Mode in the upper half of a region, while behaving as if it is in Grab Mode in the lower half. This makes it possible to avoid constant switching between these two modes.

Mouse Modes

Editing regions and their contents is very complex and, by virtue of this, requires different Mouse Modes in order to be able to perform typical editing chores in a way that is powerful and makes sense.

ModeKeyboard Shortcut
Grabg
Ranger
Cutc
Stretcht
AuditionNone
Drawd
Internal Edite

Changes to the mouse pointer only occur when hovering over the track canvas; the mouse pointer always changes to a hand in the ruler area regardless of what mode is selected, and always moves the playhead to the position left-clicked on—as long as there is no marker or other tag under the mouse position clicked on.

Grab Mode

Grab Mode is used for selecting, moving, deleting and copying objects. In this mode, the mouse pointer appears as a hand and can be used to select and perform various operations on objects such as regions, markers and etc. This is the most common mode to work in, as it allows the for selection and moving of regions, as well as the modification of control points in automation lanes.

Range Mode

In Range Mode, the mouse pointer appears as a vertical line; left-clicking on the track canvas will display the time at the position clicked on. left-clicking and dragging on the track canvas will create a time range for the track clicked and dragged on; adjacent tracks can be selected as well by dragging the mouse into them. Once a time range has been defined, it can be resized by left-clicking on either the left-hand or right-hand side of the range and dragging the mouse to the desired position.

Cut Tool Mode

In Cut Tool Mode, the mouse pointer appears as a pair of scissors and allows for the separation of any region into two distinct regions by left-clicking at the desired point of separation. If more than one track is selected, then all the regions on the selected tracks will be split at the point clicked on. If no track is selected, then only the region hovered by the mouse cursor will be split.

Stretch Mode

In Stretch Mode, the mouse pointer appears as an expanding square symbol and is used to resize regions using a timestretch algorithm. Resizing a region is done by left-clicking on the right-hand side of the region and dragging the edge to the desired position; once the button is released a Time Stretch Audio dialog will appear.

Audition Mode

left-clicking on a given region using Audition Mode will play the contents of that region (along with all other non-muted tracks). The regions can also be scrubbed by left-clicking and dragging in the direction desired; the amount dragged in one direction or the other will determine the playback speed.

Draw Mode

In Draw Mode, the mouse pointer will change to a pencil; the effect it will have depends on the type of track or region it is utilized in.

In an audio track, a green line will appear in the region which is that region's gain envelope. left-clicking anywhere in a given region between two existing control points will add one to the region at the X-coordinate clicked on with the Y-coordinate being on the line connecting the control points on either side of the new one. left-clicking on a control point will allow it to be moved to any point in the region in between the control points that bound it on either side of itself. And finally, left-clicking on a control point and pressing the delete key or holding down the key while right-clicking on it will delete the control point.

In an automation lane, if any automation is defined in it, a green line connecting its control points will appear in the lane. Control points in the lane are manipulated in exactly the same way as they are in a region's gain envelope (see previous paragraph for details).

In a MIDI track, if the mouse is left-clicked in a part of the track that has no region, a region one bar long will be created. If the mouse is dragged after being left-clicked in a part of the track that has no region, a region of arbitrary length will be created by releasing the mouse at the desired length. l-click in region depends on note mode, sustained inserts note with length of snap grid(?) while percussive enters a diamond; l-click & drag draws note of arb. length in sustained while percussive draws a succession of diamonds in the dragged area, # & type depend on grid & divisions.

Internal Edit Mode

In Internal Edit Mode, the mouse pointer will change to cross-hairs. This tool acts on region gain and automation as the Draw tool. On a MIDI region, it allows to lasso-select multiple notes at a time.