Saddle-notch Corner
A notch on the bottom of the log straddles the top of the log coming from the perpendicular wall. Both logs extend past the corner. This style is favored by many handcrafters.

Dovetail Corner
This style is used with square or rectangular logs. The corner is cut in a fan-shaped wedge and interlocks with perpendicular logs.

Butt and Pass Corner
One log stops where it meets an intersecting log, and the other log extends past the corner. In most, passing logs have a mortise (cutout) into which the butt log fits for a tight corner.

<Corner Post
A post is found at each corner into which grooves are cut to hold log ends. Looks similar to post-and-beam construction.