The "Ha" is the cutting edge. Due to differential hardening, this portion of the blade will be substantially stiffer and harder than the remainder of the blade.
The Yokote is the point line which make the transition between the body of the blade and the kissaki or tip section.
A nakago is the part of the katana blade that extends into the handle. It is the section of the katana tang that protrudes from the base of the handle.
The kashira is a small, round pommel that sits at the end of the handle and helps to balance the sword.
Menuki are small, decorative ornaments that were traditionally used to adorn the hilts of Japanese swords.
Mekugi are small wooden pegs used to secure the handle of a katana in place. The mekugi is inserted through a hole in the tang of the blade and into the grip.