You need to have a card reader on your computer.
And you need some memory card file recovery software.
There are hundred of such programs.
I only know of one such program that is free.
I have a Kodak DC210 camera which uses a compactflash picture card. I had collected about 30 pics on this card. While viewing the pics on my Acer Aspire (WIN7) lap-top using a USB adapter (Vantager card reader) the pics disapeared. I plugged the card back into the camera and got a message that the card needed to be reformatted. My question is: can the pics be recovered?