In the Linux operating system there is a very handy trick that most new users do not know about. Take a look at your mouse. How many buttons do you have? Three I bet. You may say only two but that scroll wheel...you can click it. In Linux that scroll wheel IS considered a button and it's the third (or middle) mouse button. That button has a special purpose. That purpose? Pasting copied text. How do you do it? Simple. Go to a document and, with the left mouse button, highlight some text. Now go to a new document (this will be in a word processor, web browser form, text editor, whatever), place your cursor where you want to paste that new text and click that middle mouse button. What happens? Most likely that copied text appeared where you clicked.
This method works if you highlight by dragging the mouse or placing your cursor at the beginning of a line and using Shift-Arrow Key combination to highlight the text. Either way that text will be placed in a buffer ready for you to paste. You can also use this from one application to another. You can highlight text with your mouse in a browser and then paste that text in an OpenOffice document.