Microsoft SQL Server Express is a version of Microsoft’s SQL Server relational database management system. It is free to download, distribute, and use. It comprises a database specifically targeted for embedded and smaller-scale set applications, with certain limits on database size and maximum number of cores (among other things). See https://www.microsoft.com/en-gb/sql-server/sql-server-editions-express for full details. From a SupportDesk point of view, there is no difference to the configuration for MS SQL Server. If you are running SQL Express, ensure that you download SQL Management Studio Express so that you can manage the databases and users.
We advise that you take a backup of your SupportDesk directory and databases on at least a daily basis. Contact your Company’s Database Administrator (DBA) to ensure this takes place.