All eBooks are Not the Same for Printing, Checkout and Download
They are not all the same format. Some are PDF, some are EPUB. (This is kind of like the difference between a JPEG file and a TIFF file.)
Some have limited user access (only one person can view or checkout at a time). Sometimes we own more than one copy and this can affect the number of users who can access the book concurrently.
Some can be checked out and downloaded and some cannot. All can be viewed on a PC or MAC, you don't HAVE to download.
Checkout periods vary. You can reduce the number of days you want to check something out, but you cannot extend it.
Some allow print, copy and paste. Some do not. You will find this information when you click on the title in your results screen (see example below).