With the release of Mac OS X Mavericks, you can now read iBooks on your Mac in addition to your iOS 7 device. The method you use to copy and paste depends on whether you use the mobile app or the desktop application. Copying and pasting can provide a useful option when you need to quote a section of text, although the copy function on both the app and the desktop application limits you to selecting only the currently viewable area of the text.
On Mobile Devices
Access the book in the iBooks app for your iOS 7 mobile device.
Double-tap a word and then move the grab points to select the word or multiple words in a passage to select a region of the text. Choose the "Copy" option in the bar that appears at the top of the selection. Alternatively, you can highlight the text by selecting the "Highlight" option instead. Then, tap the "Share" icon in the bar that appears and select "Copy."
Open the app that you want to use to paste the text.
Double-tap in the text area and select the "Paste" option to paste the text.
On a Mac
Click the "Go" menu, select "Applications" and double-click "iBooks" on Mac OS X Mavericks.
Double-click a book to open it.
Highlight the area of text that you want to copy by dragging your mouse over it and select "Copy" from the menu that appears when you release the mouse. You can also press "Command-C" to copy the highlighted text if the menu isn't visible.
Open the application you want to paste the text into and press "Command-V" to paste the text. You can also right-click in a document and select the "Paste" option from the menu.
The share symbol looks like a box with an arrow extending upwards.