“Pinyin is a way to represent Chinese characters and express the sounds in the Chinese language using the alphabet. There are other systems to express Mandarin, but Pinyin is the most accepted and widely used. Once you learn Pinyin you will know how to pronounce any word in Mandarin using a Chinese dictionary. Pinyin is also the most common way to input Chinese characters into a computer. Although Pinyin and English both use the Roman alphabet, many letters are not expressed with the same sounds that English uses.?

http://www.mandarintools.com
This is one of the best websites out there, containing an array of tools to help you learn Chinese. The tools include flashcards, a dictionary, a Chinese annotator, and more. One of their best tools is a program called DimSum , which integrates the various tools offered on the website into a single, easy-to-use tools that the user can install on his or her local machine. This website also contains a variety of links to other good resources on learning Chinese.

http://www.euroasiasoftware.com/english/chinese/software/index.html
uroAsiaSoftware provides three free programs to help with learning Chinese. The first is a Chinese for Beginners Program. The second is a Chinese Homework Trainer. The last is a Talking Chinese Dictionary. We found the user interface to these programs to be a bit confusing, but the enterprising student may find them useful nonetheless.