Mouse usage in Emacs by default is different than it is in other applications, and it can be confusing for an EmacsNewbie.

You can use the mouse as usual:

Check the EmacsManual to learn about additional available mouse actions. In particular:

See KeySequence and Region for more about mouse actions.

Regions and Selection

The TextCursor (not the MousePointer) defines the position of Point, which is one end of the Region. The other end is the Mark. The mark is invisible; point is indicated by the cursor.

You can set point by clicking ‘mouse-1’ or using the arrow keys. You can set the mark in any of these ways:

If you define the region without using the mouse, it may be invisible; you can make it visible via ‘C-x C-x’, which also swaps the point and the mark.

CategoryHelp CategoryMouse CategoryRegion