Dynamic data is information that belongs to individual recipients of a Web-to-SMS message contained within a Contact List or Offline Data and then inserted into the final message received by each recipient.
Although there are no restrictions with regards to the type of dynamic data or the amount which can be inserted into a message, the most popular example of dynamic data would be recipients' first & last names. Inserting these two pieces of dynamic data within the message body would enable recipients to be addressed personally.
Dynamic data is inserted using the drop-down menu shown above the message box and directly reflects the field-names in the source data. When inserted into the message body, they are wrapped in {curly brackets} and these denote that they are dynamic and should be replaced with recipient data.