Over 60% of the file size of the average web page is taken up by graphics and multimedia. So graphics optimization is an important step in optimizing web page speed. At an alarming frequency, we have seen large PNG24 and unoptimized JPEGs used on the Web. Large PNG24s should be optimized for file size or converted to PNG8s. This article shows how to optimize PNG files effectively by minimizing their color palettes, and using alpha transparency intelligently.