The System Logs page will show you the different transactions that your eCommerce site has executed. This can vary from account logins, to sales generated to cron tasks run.
You can view your system logs by clicking on Settings > System Utilities > View System Logs
You can delete your transaction logs by clicking on the Prune Log button in your View System Logs page. Alternatively, eCommerce Suite will prune your transaction log through your CRON job every 30 days by default. You can change this setting by editing the Cron Transaction Log Interval in Settings > Automation tab > Cron Job tab