I've been working with AutoCAD longer than I care to mention. I'm used to selecting items in just a few ways:
1. Selecting object individually, by picking them.
2. Windowing around object(s).
3. Crossing object(s).
4.Using mulitpoint (polyshape) crossings. Which AutoDesk has made a little easier with their new selection tool.
AutoCAD 2015 introduces a new option for object selection - "LASSO".
Selecting objects by drawing a freehand boundary curve (similar to raster editors or Fusion 360) can be activated by pressing and holding the left mouse button and dragging along the requested boundary.
Similarly to selecting with a rectangular window, dragging to the left invokes crossing selection, dragging to the right invokes full enclosing (the whole object must be caught in the lasso).
Both modes can be toggled by pressing the spacebar during dragging (do not depress the mouse button). A second spacebar press switches to the Fence mode - will select objects intersected by a freehand curve you draw by dragging.