Source : Free On-Line Dictionary of Computing

First Fit
     
         A {resource} allocation scheme (usually for
        {memory}).  First Fit fits data into memory by scanning from
        the beginning of available memory to the end, until the first
        free space which is at least big enough to accept the data is
        found.  This space is then allocated to the data.  Any left
        over becomes a smaller, separate free space.
     
        If the data to be allocated is bigger than the biggest free
        space, the request cannot be met, and an error is generated.
     
        Compare {Best Fit}.
     
        (1997-06-02)