Pochades are small paintings, painted plein air, either to be used as references for larger, studio-based pictures, or as ends in themselves. The word derives from the French for pocket: poche.
Because of the portability of the format, they are often used for painters when travelling, and manufacturers cater for this with "pochade boxes": wooden boxes to hold palettes, brushes, paints and the paintings themselves.
I do not use such a a box, however. I use a French easel as I like to stand when working, and I carry pictures around in little folders, which I refer to as carriers.
There are pochades by a diverse range of artists, typically ninetheenth and early twentieth century, when plein air painting really came into vogue. These include John Constable (in my opinion easily his liveliest pictures are pochades- you can see a supurb set in the Victoria and Albert Museum), Corot, and J.D. Fergusson (whose tiny pochade box is on display at Edinburgh's Museum of Modern Art).
Primed card ready to be used for painting. These cards are about 14 cm long.
.My pochades are in oils, and are intended as final pieces. I want live performance in art, not work tidied, made polite, in a studio. I've been working on these small pictures for about six years but it took a couple of years for me to reach a good level of technical fluency with them.