Shandy is beer mixed with a clear carbonated lemon-lime drink or a clear lemon-flavoured beverage, and many variations thereof. In Europe, New Zealand, and Australia, this clear lemon-lime soda is referred to as "lemonade," and when mixed with beer it is called "lemon shandy".

The proportions of the two ingredients are adjusted to taste, but are frequently half lemonade and half beer. Shandies are popular in Europe, Australia, New Zealand, South Africa, and Canada (where they are sometimes known by the French name 'Panaché').

In some jurisdictions, the low alcohol content of shandies makes them exempt from laws governing the sale of alcoholic beverages. Non-alcoholic shandies are known as "rock shandies".

'Biermischgetränke' ("beer-based mixed drinks") are popular in Germany. Sometimes, non-alcoholic beer is used, so the drink has no significant alcohol content. A common ingredient of these drinks is German-style carbonated lemonade.

In Berlin and eastern Germany, the Potsdamer, a 50/50 mixture of light-coloured beer and flavoured soda, is a popular drink. The soda used in a Potsdamer is flavoured with a shot of raspberry syrup, giving it a red colour.

More Info: en.wikipedia.org