Selection Bar

From Audacity Manual

The Selection Bar (above) is normally at the bottom of your Audacity window, but like any of the Toolbars, you can move it wherever you want by dragging the grab bar on the left side of the bar. Selection Bar shows and allows editing of :

• Project Rate: The sample rate for the project, typically 44100 Hz. Changing this value immediately changes the sample rate at which new tracks will be recorded or generated, and at which existing tracks will be played back, mixed or exported.
• Snap To: If checked, selections and mouse clicks snap to the currently chosen units. For example, the units in the image above are set to hours:minutes:seconds. With Snap To enabled and the cursor at the start, clicking in the track at 2.8 seconds causes the cursor to jump to the nearest preceding unit, in this case 2.0 seconds. To change the units to another format such as samples or CDDA frames, click the downward pointing arrow in any of the three boxes to right of Snap To. See Audacity Selection for advanced usage of the Selection Bar.
• Selection Start: If there is no selection, this shows the cursor position.
• (Selection) End/Length: Click the "End" radio button to show the end point of the selection. If there is no selection, the value is the same as the Selection Start. Clicking the "Length" button shows the length of the selection instead (the value shows as zero if there is no selection).
• Audio Position: Displays the current real time position of playback or recording.

Individual digits in the numerical entry boxes can be edited directly so as to change the cursor position or selection area. Click on the digit and then either use the mouse wheel, or use the up and down arrow on the keyboard to increment the value.