When one needs to send a large number of files by email or across the internet by whatever means (such as ftp), it can be a savings of time (transfer time) if those files are compressed or packaged before sending.

There are a variety of programs which handle this process. One common program is called "STUFFIT" (which is not just an exasperated Brit, but rather the name of Software). Go to stuffit.com for more info on this product.

I am not clear as to what data loss occurs when stuffing photos for print - and thus for the transfer of art photos and other photos intended for print output, more research is warranted, but for most files it is my opinion that this is the way to go to reduce file size !