If you opt-in to receive my newsletter, you will receive weekly (or sometimes just twice monthly) mailings where I highlight sales, new releases and other book recommendations.
The data is stored securely by the mailing list host, Mailchimp. Such mailing list providers also provide various link tracking software in order to better deliver campaigns to you.
Each newsletter has an unsubscribe link at the bottom. You can unsubscribe at anytime. Once you unsubscribe, your data is removed from the system.