A birthday cake in Western culture is a pastry or dessert served to a person on his or her birthday, usually decorated with the person's name and/or a message of congratulations. It is often decorated with candles, one for each year the person has been alive. One tradition is to add an extra candle "for good luck," although this varies. The candles are lit and everyone (except the person whose birthday it is) sings "Happy Birthday to You."

Tradition holds that the person with the birthday can make a wish, which will come true if all the candles can be blown out in one breath. But many people make a wish if it takes them more than one breath. Another tradition is to smear out the name of the person for good luck before slicing the cake for serving.

Birthday cakes are usually sponge cakes, although many other designs can be used. One of the most popular flavors is chocolate.

The U.S. patent #6,319,530 is a "method of photocopying an image onto an edible web for decorating iced baked goods." This invention enables one to inkjet print a food-grade color photograph on the cake surface.