Internet traffic Overheads

[#1]

Hello. I have just become a plusnet customer and was pleased with the 10G allowance. However, I've notice that when I let my PC sit idle and using a basic  traffic monitor (NETWORX) , that there seems to be a lot of internet traffic.  I think one of the culprits is SKYPE, when its open its the largest contributer of traffic.  I left my PC on for about 4 hours and I had accumulated about 400MB of internet traffic.  This is not good news.  Can anyone give me some advice to reduce my internet traffic overheads when Im not actually browsing.  I notice I have a lot of services active.   
Can anyone also comment on whether I should use "Chrome" rather than internet explorer to reduce the overheads?
Thnaks for any advice
Jason

[#2]

welcome to the forum
Do you need to leave Skype running?,
I have two people using my value connection and count it as a bad day if it goes over 250M during the paid period
Its free between midnight and 8 am, all use during that time doesnt come off your 10G

[#3]

I would like to leave skype on, but can log out and log in occasionally. there is also a lot of other internet traffic, especially "receiving".  I've noticed that Skype on my android phone is always on (not using my home wifi!) and it uses far less.    I was wondering if there were any free software that could identify the main internet traffic use.  Also when I view a webpage, my usage increase by around 50MB.  Quite large I though.

[#4]

@jbryant61
I'd have thought that networx would have done that for you. Otherwise Wireshark is a bit more in depth so you might want to give that a try.

[#5]

The reason that Skype use some much traffic is

Quote

Unlike other VoIP services, Skype is a peer-to-peer system rather than a client–server system, and makes use of background processing on computers running Skype software; the original name proposed – Sky peer-to-peer – reflects this.

[#6]

the free netlimiter 2 mon version shows the usage breakdown http://www.netlimiter.com/download.php