As mentioned on other pages, the use of Digital Rights Management (DRM) prevents unlimited copying and printing from ebooks on this platform. The ebooks here come from different publishers who all have different rules about how much printing and copying can be done in one 24-hour period. If the print allowance is 50 pages per day, then today you can print 50 pages and tomorrow you can print a different 50 pages.
Printing and copying rules might be a bit complicated so we'll try and keep this simple.
There are three ways of reading an ebook:
Regarding printing and copying:
The print and copy allowances can be found in the Contents tab of the left-had column in the online reader
In the online reader, click the Print pages link 
You can print:
You can save your pages as a PDF or print them out
Highlight a portion of eBook text and use your browser's copy function (Ctrl + C) to copy the text. In practice, copying from the online reader can be inconsistent and you may find downloading a page or chapter and copying from the file you have downloaded works better.
