Wikipedia, the free encyclopedia, describes an easel as upright support used for displaying and/or fixing something resting upon it.
The word is an old Germanic synonym for donkey (compare similar semantics); its equivalent is the only word for both animal and apparatus in various languages, such as Esel in German and Afrikaans and earlier ezel in Dutch (the easel generally in full schildersezel, 'painter's donkey'), themselves derived from Latin Asinus (hence ass), interestingly in Danish the word is staffeli and donkey is æsel. We’ve come a long way...
Easels are known to have been in use since the time of the ancient Egyptians. In the 1st century, Pliny the Elder makes reference to a large panel placed upon an easel.
It is most often used to hold up a painter's canvas or large sketchbook while the artist is working or to hold a completed painting for exhibition. The simplest form of an artist's easel, a tripod, consists of three vertical posts joined at one end. A pivoting mechanism allows the centremost post to pivot away from the other two, forming a tripod. The two non-pivoting posts have a horizontal cross member on which the canvas is placed. A similar model is fit to hold a blackboard, projection surface, placard etcetera. An easel can be full-height, designed for standing by itself on the floor. Shorter easels can also be designed for use on a table. Easels are typically made from wood, aluminum, brass or steel.
There are three common designs for easels:
Tripod designs are based on three sections. Variations include crossbars to make the easel more stable and an independent mechanism to allow for the vertical adjustment of the working plane without sacrificing the stability of the three legs of the easel.
H-Frame designs are based on right angles. All posts are generally parallel to each other with the base of the easel being rectangular. The main portion of the easel consists of two vertical posts with a horizontal crossbar support, thus giving the design the general shape of an "H." Variations include additions that allow the easel's verticality to be adjusted.
Folding designs are based on two sections hinged together. These modern designs provide great options of functionality and savings in storage.
There are three common usage for easels:
Studio easels are meant for use in the artist's studio with limited need for the easel to be portable. Studio easels may be simple in design or very complex including winches, multiple masts and casters. The largest easels are studio easels with some being able to support weights of over 200 lb. and panels over 7 feet in height.
Field easels are meant to be portable and for the creation of en plein air work. These easels are usually mid-sized or small, have telescopic or collapsible legs and are based on the tripod design. French box easels include a compartment in which to store art supplies conveniently along with a handle or straps so that the French box may be carried like a briefcase or a backpack.
Display easels are meant for the display of finished works. These easels tend to be very simple in design with less concern for the stability needed by a working artist. Display easels can vary in size and sturdiness depending upon the weight and size of the object to be placed on them. Today, competition and trends in display have created amazing designs to attract the discerning customer for their dollars.