We can divide the appearance of animals into two - the basic pose, and the head position. Most of these apply to any quadruped, but (with the inevitability of such things) some positions get a different name for specific critters. So... onwards, with the most common poses or attitudes:
With me so far? In addition to the above, there's affronté, which means 'facing the viewer', usually with front paws down as a cat might sit, and dormant (like couchant but with its head tucked in as if asleep). To add to the fun, salient is forcene for horses, climant for goats, and springing for deer. Also, there's erect (stop sniggering at the back) which means walking on two legs.
Note also that all these are facing left. Creatures facing right are said to be to sinister or contourné.
Cool. Now, the default head position for all these poses is with head facing in the same direction as the body. If the head is facing the viewer in any of the sideways-on poses, it's termed guardant. If it's facing backwards along the animal's spine as if looking over its shoulder, it's regardant (note, no 'u'!).
So, with that in mind? Your teaser for this week: figure out what the following blazons look like, and tell me which arms they are a part of. (The ones ending with an ellipsis are incomplete blazons, and they're all from somewhere in Britain.)
- Gules, three lions passant guardant in pale or, armed and langued azure.
- Or, a lion rampant gules armed and langued azure...
- Gules, a bear erect argent, muzzled of the first, collared and chained or...
 Quite why there's a fascination with blue claws and tongues on heraldic lions I'm not entirely sure!
 I can't remember if I mentioned this earlier, but it's a heraldic affectation to refer to a previously mentioned colour (so in this case, 'of the first' means 'gules', 'of the third' would be 'or', etc.).