Check if you have an account that has been compromised in a data breach
Important notice regarding the Ashley Madison data: only those who have subscribed for notifications and verified their email address will be able to discover if they were in the breach due to the sensitivity of the data. You can read more about the rationale of this approach here.
No breached accounts and no pastes
A "breach" is an incident where a site's data has been illegally accessed by hackers and then released publicly. Review the types of data that were compromised (email addresses, passwords, credit cards etc.) and take appropriate action, such as changing passwords.
A "paste" is information that has been published to a publicly facing website designed to share content, usually anonymously. Often these are indicators of a data breach so review the paste and determine if your account has been compromised then take appropriate action such as changing passwords. Pastes are often removed shortly after having been posted. Read more on the pastes page.