Summarize the traditions and activities associated with birthday celebrations in Britain as described in the text.

In Britain, birthday celebrations involve a party where everyone brings a small gift. A mum often makes a birthday cake. The celebration includes a table full of food such as crisps, sandwiches, small cakes, chocolate biscuits, ice cream, and small sausages on sticks. The house is decorated with balloons, and party games are played with friends.