Here's a screenshot of the error log for an instance of SQL Server 2008 for reference, along with an enlarged version for easier reading.
The view in the screenshot is from Log File Viewer in SQL Server Management Studio. The log file entries are sorted with the oldest logs at the bottom. The actual error logs are just text files, so you can use Notepad or your favorite text editor to view the log files. By default, SQL Server keeps the current log plus the past six cycled logs. Log File Viewer tries to do some basic parsing and is handy because you can also merge in views of other logs, such as the Windows system logs.
Read more: PTC Windchill on SQL Server