You can insert randomly generated text into messages. It will be different in each message you send and every message will be unique. Please select the “Insert” / “E-mail merge data” / “Random text” command to add the random text tag to the message. In the new dialog box, you should specify the text generation options.
You can set the minimal and maximal length of the text and specify characters for the text generation. If you apply the settings from the screenshot below, Atomic Mail Sender can generate the following strings:
Random text can be used to add more email personalization to the messages. For example, you can generate unique user IDs automatically and track users (by the way, the best way to track messages is explained here).