Bezier with Pen Tool
Bezier Curves, available in the Pen Tool, enables you to draw smooth curves with precision.
How to use Bézier
To create a Bezier curve in Inkscape, click on the
button in the Toolbox, or press b or Shift + F6.
Left click to create the first node.
To draw a segment, just click again further where you want the segment to end. Inkscape immediately draws a straight line between these two points.
Delete a Segment
To erase the last segment/node, press del.
Draw a Curve
If you want to draw a curve, keep the button pressed after clicking and drag to make curve control point appear. They are symmetrically placed to make a perfect smooth curve so that you also need to move only one node. To stop drawing the actual curve you can either click the first node of the global curve (if you want it to be a closed shape), or press Enter or double-click.

Continue a Path
To continue a path that has been previously drawn, just press b to activate the pen and click on either the beginning or the end.
A pen made path can be continued with the pencil F6 if needed.
Tips
A right-click closes the shape but doesn't add any new points. It then becomes a path that you can edit with any other tool, especially the Node Tool F2.
Further editing of any curve can be accomplished with the Node Tool.