What is database server for desktop and do I need it?

[DouglasGreenfield]

This is one of the installs listed for ArcGIS 10.4.1.  I already have database server connections set up in Catalog. Is there a reason I should install this? 

[DanPatterson_Retired]

Existing ArcGIS for Desktop users—Help | ArcGIS for Desktop says yes for license manager but remains silent (probably meaning yes) for the others.

[George_Thompson]

I think you are looking at this.... Database servers—Help | ArcGIS for Desktop

This is a completely separate product that is not required to use ArcGIS for Desktop. I would not use it unless needed, too many limitations in my opinion.

Here is more details on database servers: Types of geodatabases—ArcGIS Help | ArcGIS for Desktop    - Look at the section - How is ArcSDE technology included in ArcGIS?

Geodatabase​

Hope this helps!

[AsrujitSengupta]

Database Server for Desktop is the new name for "ArcSDE Personal". It comes free with ArcGIS Desktop.

The link that George provided should give you more details.