MMS stands for Multimedia Messaging Service. It is a mobile phone service that allows a subscriber to attach pictures, short video clips, and music clips to a message.
Before MMS the only means for data messaging was the Short Messaging Service (SMS). To use MMS service you need a GPRS, EDGE, 3G, or 4G phone. To access the MMS service your mobile phone must have the capability.
The recipient of such a message should also have a mobile phone with multimedia capability, otherwise an SMS message will be sent referring them to a website were they will access the MMS message.
With MMS you can reach to your friends and loved ones in more than just the limited text capability of the SMS. You can send greeting cards and pictures to friends and family.
However, MMS seems to be lagging behind SMS. With more people having mobile phones with camera one would expect MMS to be having an explosive growth. But consumers prefer to share photos and video via sites like Facebook and Twitter, limiting the use of MMS.