Just to elaborate on Doc's point.
Type L in the command bar, click on two spots: you have a line
Type L in the command bar, write the coordinates of first point, then the coordinates of second point: you have a line
Type L in the command bar, click or write the coordinates of first point, then an angle and a distance: you have a line
Click on the line, you get its properties
Click on some snap points of the line, you can modify it
It's precise. Not everyone needs that kind of precision.
Try to draw some blueprints on Photoshop or Gimp: you'll suffer.
Try to draw some anime character on AutoCAD: you'll suffer.