cocktail shaker

A cocktail shaker is a device used to mix beverages (usually alcoholic) by shaking. When ice is put in the shaker this allows for a quicker cooling of the drink before serving.

Usage
A shaken cocktail is made by putting the desired ingredients (typically liquor, fruit juices, syrups, liqueurs and ice cubes) in the cocktail shaker.
Then it is shaken vigorously for around 10 to 18 seconds, depending upon the size and temperature of the ice.

Varieties
There are at least three varieties of cocktail shaker:

The Boston Shaker: A two-piece shaker consisting of a 28 imp fl oz or 800 ml metal bottom and traditionally a 16 imp fl oz or 450 ml glass or plastic mixing glass. The mixing container and bottom are inserted into each other for shaking or used separately for stirring or muddling. A separate strainer, such as a Hawthorne or Julep strainer, are required for this type shaker if crushed ice is used. Without such a strainer, some bartenders may instead strain by narrowly separating the two pieces after shaking and pouring the drink through the resulting gap. The market offers now 18 imp fl oz or 510 ml and 20 imp fl oz or 570 ml container versions too. Beginning in the late 1870s and early 1880s, versions of the Boston Shaker appeared with the metal bottom piece containing integral strainer mechanisms.
The Cobbler Shaker: A three-piece cocktail shaker that has tapers at the top and ends with a built-in strainer and includes a cap. The cap can often be used as a measure for spirits or other liquids.
The French Shaker: A two-piece shaker consisting of a metal bottom and a metal cap. A strainer is always required for this type of shaker, barring the separation method mentioned above.