Kamae (Stance)

There are a number of kamae (stance; fighting posture) found in the art of Kendo.  Some have more practical use than others in fighting, and others are pretty exclusive to Kendo Kata.  As a brief overview, here they are:

Chudan is the most basic, most standard kamae used in kendo.
Looks like this:

From the side, it looks like this:

When facing an opponent, the tip of your shinai should be pointed at the opponent's throat.
If you are not facing an opponent, the tip of you shinai should be at the level of your own throat.

When kendoka speak of Jodan, they typically refer to HIDARI (left) JODAN, which has the practitioner with his left foot forward (whereas most kamae have the right foot forward) and the shinai is held over the head at a slight angle.  Hidari-Jodan is the standard Jodan kamae.  MIGI (right) JODAN incorporates the same foot position as Chudan-no-kamae (right foot forward) with the shinai held over the head in a straight line.  AGE-TO is a variant of Jodan-no-kamae where the practitioner holds the shinai overhead with only one hand.

Migi-jodan is not completely uncommon in kendo shiai, but it is more recognized in Kendo Kata Ipponme (#1) for Shidachi.

Hidari-Jodan looks like this:

Gedan's most standard use is in Kendo Kata Sanponme (#3) for both Shidachi and Uchidachi, and again in Kata Ropponme (#6) for Shidachi.  A "modified" Gedan is occasionally used (at risk!) by some players during shiai, often as an attempt to lure an opponent into breaking his own kamae.

In the image below, note the upper picture illustrates proper Gedan for Kendo Kata, while the lower picture illustrates the typical "modified" Gedan used in kendo shiai:

Hasso is used almost exclusively in kata, specifically, Kendo Kata Yohonme (#4) for Uchidachi.  Hasso is a variant of Jodan-no-kamae and there can be both a 'right' and 'left' side with Hasso.  Typically, Hasso-no-kamae is adopted with the left foot forward, the left hand in the center of the chest, the tsuba near the mouth, and the sword itself slightly angled over the right shoulder.

In kendo shiai, Hasso-no-kamae is typically a transitional kamae when moving from Chudan to Hidari Jodan.  This may not be the proper way to articulate things, but Hasso could also be understood as a position from which Katsugi-waza is launched by an attacker (check YouTube for video examples).

Waki is exclusively used in kata, specifically, Kendo Kata Yohonme (#4) for Shidachi.  It arguably has absolutely zero value in modern kendo shiai.  It looks like this:

For informational purposes, it is worth noting that Kendo regulations permit the use of two sword in shiai (NITO-RYU).  Kamae for nito-ryu can vary with either the left or right foot forward, with the daito (long sword) and shoto (short sword) held in either the right or left hand: