In the US, cider is unfermented unfiltered apple juice. It is occasionally still sold unpasturized which is considered to have a better flavor. The possibility of salmonella means that most apple cider is pasturized. Because it is unfiltered, apple cider is opaque from suspended solids as opposed to apple juice. Apple ciders are often made from blends of several different apples to give a blaanced taste. Hard cider is an alcoholic apple drink.
In the UK, cider is an alcoholic drink brewed from apple juice. It is predominantly (but by no means exclusively) brewed in the south west of the country. Cider is often stronger than beer, and will frequently be over 6% alcohol by volume.
As with other drinks, ciders comes in a variety of tastes, from sweet to dry. As with other sweet drinks, sweet cider tends to be popular with young people. As such cider is often the drink of choice for teenagers in the UK (along with alcopops).
Modern ciders are generally heavily processed, and resemble sparkling wine in appearance. These are called hard cider in the U.S. More traditional brands, often known as scrumpy, tend to be darker and more cloudy, as less of the apple is filtered out. They are often stronger than processed varieties. In very large quantities (in excess of 2 gallons per day) scrumpy can cause temporary blindness due to trace amounts of arsenic found in apple seeds. Such consumption is extremely rare.
An old practice with cider is the making of Applejack, where a barrel of cider is left outside during the winter. When the temperature is low enough the water in the cider will start to freeze. If the ice is removed, the (now more concentrated) alcoholic solution is left behind in the barrel. If the process is repeated often enough, and the temperature is low enough, you can make some very strong spirit indeed.
Famous brands of cider