Signature file (PopMail)
SIG is a signature file format used in POPMail. SIG files are usually placed at the end of an email, and usually contain information such as a business name and contact information. POP stands for Post Office Protocol, and is currently in its third version (POP3). POP3 is used by most e-mail servers, such as Gmail and Outlook Express.
Learn more about .SIG files:
Learn how to create ad-aware signature files for Microsoft Outlook.
Search on IT Knowledge Exchange for .SIG-related questions.