A cheesecake is a sweet, cheese-based dessert. The combination of its crust and filling (typically containing eggs, cream, and a soft fat like cream cheese) make it a closer relative of custards like buttermilk pie or creme brulee than of a traditional cake, and in fact it is classified as a pie (and not a cake). The first recorded mention of cheesecake was during the ancient Grecian Olympic games in the occidental world. Cato the Elder wrote of cheesecake preparation in his farming manual "De Agri Cultura".
Cheesecakes can be made of ricotta cheese, havarti, quark or, more usually, cream cheese. Other ingredients such as sugar, eggs, cream and fruit are often mixed in as well. Flavorings such as vanilla or chocolate may be added, and a fruit topping, like strawberries, is frequently added. Typically, the cheese filling or topping covers a crust, which may be pastry, cookie, digestive biscuit or graham cracker-crumb. Sometimes the base is a layer of cake.
A common difficulty with baking cheesecakes is its tendency to "crack" when cooled. This is due to the coagulation of the beaten eggs in its batter. There are various methods to prevent this. One method is to bake the cheesecake in a hot water bath to ensure even heating. Other methods include blending a little cornstarch into the batter to prevent the coagulation of eggs or baking the cheesecake at a lower temperature and slow cooling it in the oven, turned off, with the door ajar. If these methods fail, a common practice is to cover the top of the cheesecake with toppings such as fruit, whipped cream, or cookie crumbs.
In the UK, cheesecake is generally a cold dessert which is neither cooked nor baked. It is made with crumbled digestive biscuits mixed with butter and pressed into a dish to form a base layer. The topping or filling is a mixture of milk, sugar, cheese, cream and, sometimes, gelatin.
The word cheesecake is also used to describe the creamy, cheesy flavor of the dessert. In this usage, there are cheesecake yogurts, ice creams, brownies, and cookies.
There are also savory cheesecakes, often flavored with blue cheese and served as hors d'oeuvres or accompanying salads.

Culinary uses and challenges for different types of cheesecakes

Junior's
The Cheesecake Factory