What is updated by each "update" task during ODA patching

I've just started preparation for rolling out the 18.7 release to our ODA estate and noticed some extra "update" steps.

e.g. The key stages to patching the ODA to 18.7 are :

update DCS agent

update DCS admin (new for 18.7)

update DCS components (new for 18.7)

update server

update storage

update db-home

I know what the "update server" and "update db-home" steps do but I don't have a clear idea of what is affected by the other steps and I can't find any clear documentation that details this.

Can anyone shed light on what the various "DCS" updates are impacting ?

Also, what does the "update storage" step actually do ? Is it applying firmware updates to the disks or modifying the ASM configuration to reflect the latest GI release etc. ?