Both of these expressions are used when someone has done far, far more than was required of them. Have a look at the following examples:

   – Sergeant McCrosky received a medal for Service Above and Beyond the Call of Duty for saving that drowning girl last week.
   – Melanie in customer service really went the extra mile for me, and solved all of my computer problems!
   – My assistant regularly goes above and beyond for me, which is why she gets such a generous Christmas bonus in addition to her excellent salary.
   – The software team really went the extra mile to make sure that all computer users could easily operate the new system.

Image courtesy of Witthaya Phonsawat / FreeDigitalPhotos.net

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