Take one minute of video. Look at the file size. Now how many of these 1 minute files can you fit onto an 8GB card in your particular format and camera/device.
SMS stands for Short Message Service, which is the formal name for text messaging. It's a way to send short, text-only messages from one phone to another. These messages are usually sent over a cellular data network. That's not always true, though, as in the case of iMessage below.
SMS stands for Short Message Service, and it is synonymous with text message, text, TXT, etc. An SMS (text message) is a short message, which can be sent to and from a cellular phone. Nearly all phones purchased in the last ten years are capable of sending and receiving text messages.