overhead

I see this term used a lot when it comes to overuse of memory, but I don't know in depth if it is really that. I noticed tha ... he term overhead mean in detail? is there any relationship between overhead and objects? how to pronounce overhead? :)

I just read about physical design and database tuning and I couldn't understand the concept of overhead, and consequently I c ... red by the answer quoted above, then I will remove it. Book : Database Systems, 2011. Elmasri R, Nevathe B, chap 20, pg 495.