The SMS logs table shows a list of SMS messages that have been sent for a period of time within the system. It contains information about the sms id, phone number of the recipient, type of the message, it's status (new, sending, sent, error, expired, attachment error), added/sent time and details of the message.
There is a filter at the top-right corner of the table that can be used to view SMS messages for a particular Period of time, Type of message (e.g. message, test, add-on, monitoring, scheduling notification) and Status (new, sending, sent, error, expired, attachment error).
You can view the message by clicking on the icon in the Details column.