A colorful burro suspended from a tree is probably the image that comes to many people's minds when they think of a pinata. Donkey pinatas have become quite iconic of Mexican celebrations, especially children's birthday parties–but with origins in China, the pinata tradition has evolved over the centuries and continues to be a source of inspiration for many different festivities.
Centuries ago, pinatas were a New Year's tradition in China. The Chinese filled decorative oxen and cow figures with seeds and hit them with "colorful sticks" so they would fall to the ground and be burned later–the ashes were then "collected for good luck". On a visit to China, Marco Polo observed this tradition and during the 14th century, it made its way into Europe.
The new European pinata resembled a clay vase and was called "pignatta", or "fragile pot" in Italian. The tradition of hitting the pinata then reached Spain and became associated with the celebration of Lent. When pinatas were brought to North America by Spanish missionaries, they found that the Aztecs had their own version–clay pots placed in front of the temple of their war god that were filled with devotional items and intricately decorated.
What became the traditional Mexican pinata, was a seven pointed star rich with symbolism, as the traditions in cultures before it. The seven points symbolized the seven deadly sins in Christianity, the fruit and candy typically used to fill it represented life's temptations, and the blindfolding of the person with the stick symbolized blind faith in fighting evil. The act of hitting the pinata then became an act of defying evil.
Though the symbolism of breaking a pinata no longer carries the same meaning, pinatas continue to be tweaked and changed, and most recently during the zeitgeist of DIYers and event planners who create them for different festivities (i.e. the metallic diamond pinata). And of course, there is always the burro pinata.