The currency in the Philippines is the Philippine peso (or piso). ISO standard code is PHP. The peso is divided into 100 centavos (or centimo).
Since December 2010 the Philippine Central Bank (Bangko Sentral ng Pilipinas) is replacing the old banknotes. The Central Bank first announced that the old banknotes will remain valid during 3 years. Now, by end of 2014, there are still millions of old banknotes circulating.
Current are coins of 1, 5, 10, and 25 centavos and 1, 5 and 10 pesos, and bank notes of 20, 50, 100, 200, 500 and 1000 pesos.
Be careful with the 20 and 50 peso notes. They are nearly of the same color and in a batch of 50 peso notes you may find some of 20 pesos.
The coins do not change in size, weight and color. But they design may change every year a little bit.