What does DSCP mean for an unmanaged switch?

Question

While investigating options for better quality-of-service on my LAN I read about DSCP (Differentiated services), which is an updated version of the good old ToS (Type of Service) in the IPv4 header.

I also found that my switches supports DSCP, but I would like to know how these packets are treated. Let's take my Netgear GS105 5 port switch as an example. The datasheet has this to say:

Traffic Prioritization
[…] Support IEEE 802.1p and DSCP-based QoS for delivering data based on priority and type

Great! Just what I need. There is also a table (shortened):

Quality of Service (QoS)
DSCP: Yes

But what does this actually mean in practice? Is there a published standard for exactly how the different classes and bits will cause packets to be prioritized in something that claims to support DSCP?

From having been a simple priority it is now spread over 14 RFCs using expressions like "code points" and "Assured Forwarding behavior group" etc. From reading the article on Wikipedia it is unclear to me how a switch would prioritize between Telephony, Multimedia Conferencing, and Real-Time Interactive.

I understand that this may be up to the individual manufacturer to design, but I'm looking for what an experienced network person would assume when seeing the DSCP label on an unmanaged switch.

I also fully understand that as soon as a packet leaves my LAN and goes out to my ISP, all bets are off, but that's not what I care about at this point.