Copying worksheets or data to other spreadsheets

Hi,

I have data in a spreadsheet which needs to be copied (sometimes the
entire worksheet and other times just some of the data) to other
spreadsheets. All of the files exist within one folder and all
filenames remain constant. What code do I need to include in my macro
to open the specified files and copy the data in? Although all files
are in the same folder, the folder name and location does change. As
many files will need to be updated I wanted this to be automated so
multiple files could be opened, worked on, and then closed.

Any ideas?

kind regards,
Matt