Sharepoint session difference with asp.net session?

Hi Expert,

I have question regarding difference between "enabling sharepoint session" and "asp .net 's session"

I have check my sharepoint using  "Get-SPSessionStateService". It reported that it was disable.

Then i go to check the corresponding IIS 's asp configuration but found out that Session properties=> Enable Session State = true.

My question is what is the difference between 2? If my sharepoint farm solution has been idle > 20 minutes, system would report error. Seems the asp session state is in effect.