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Blender really excels at animation, and the Timeline window is like having your own VCR controls at your fingertips. The timeline window, identified by a clock icon, is by default in the SR:4-Sequence screen layout just above the button window.

[edit] Timeline Window

The X-axis of the window is the timeline of your animation in frames. Frames are the fundamental unit of measure of time in Blender. LMB -clicking anywhere in the window brings Blender and all the other windows to that frame in time. Moving the mouse while holding MMB or AltLMB pans the timeline to the left or right. Holding CtrlMMB scales the display (frame range) in or out by moving the mouse left or right, just like in the 3D window.

Any Ipos (keyframes) for the currently selected object appear as vertical yellow lines at the frame they occur.

The exact frame is shown in the frame counter in the Timeline header, as well as the Buttons header. To the right of the frame counter are your standard VCR controls to rewind, skip back, play or pause, skip forward and skip to the end, and record. The start and end are set using the fields to the left of the frame counter, and synchronize automatically with the start and end frames in the Render buttons underneath the Anim button.

The menu consists of choices to View, Frame or Playback

[edit] View Menu

This menu controls what you view and how you view it:

• maximize display is a standard window feature to make this window full-screen.
• If Lock Time is enabled, all other windows are automatically synchronized to this window as the master clock.
• View All automatically zooms the display to show all events (Ipo keyframes) in range, so you don't have to pan.
• Center view centers the display on the current frame.
• Jump command do the same as the buttons in the header.
• Based on the frames per second you have set in the Render buttons, toggling the Show Seconds changes the display from frame units to seconds and fractions thereof. Very often storyboards are laid out in seconds; choosing this display unit makes things a little easier than doing all that multiplying in your head.
• Play back plays the animation from start to end. It keeps playing until you click the pause button (the two vertical lines).

[edit] Frame Menu

The Frame menu does something using the frame of animation:

• Set as... sets the current frame selected as the start or end frame as your range.
• Setting a Marker creates an orange pointer. Controlling the name of the marker by CtrlM allows you to give a meaningful name to what is happening at that moment in time, such as "Boy loses Girl" or "Soda can spritzes". Using these Markers allows you to annotate the storyboard and animation sections. Of course, you can Grab, delete and duplicate markers.

[edit] Playback Menu

Playback controls how the animation is played back, and where.

• Set Frames/Sec allows you to change the speed of your animation.
• Windows enable the types of windows to be updated with each frame during playback. Otherwise, to conserve CPU power and allow smooth playback, some window updates can be disabled.

[edit] Markers

Markers are used to denote frames at which something significant happens - it could be that a character's animation starts, the camera changes position, or a door opens, for example. Markers can be given names to make them more meaningful at a quick glance. When you create a marker in the timeline window, it also appears in the IPO, Action, NLA, and Audio windows, and vice versa, allowing you to see where the significant points of your animation lie, whichever window you are in.

[edit] Creating Markers

The simplest way to add a marker is to move to the frame where you would like the marker to appear and press M.

Alternatively, you can either press AltA or the Play Timeline button to make the animation play, and then hit M} at the appropriate points. Once you stop the playback, the markers will appear. This can be especially useful for marking the beats in some music.

Once you have made a marker, use RMB to select it, and CtrlRMB to select multiple markers.

[edit] Naming Markers

Having dozens of markers scattered throughout your timeline won't help you much unless you know what they stand for. You can name a marker by selecting it, pressing CtrlM, typing the name, and pressing the Okay button.

[edit] Moving Markers

Once you have one or more markers selected, press G to move them, and confirm the move with LMB or ↵ Enter. If you hold Ctrl while moving them, the markers will move in steps corresponding to one second - so if you have 25 fps set, the markers will move in 25-frame steps.

[edit] Deleting Markers

To delete the selected marker(s) simply press X and confirm with LMB .