In one sentence, describe what the following article is about:

Go to https://www.facebook.com/ in your browser. This will open the Facebook News Feed if you're logged in. If you aren't logged into Facebook, enter your email address (or phone number) and password before proceeding. Look for a status or a comment that you want to copy. If you're trying to copy text from a website or source other than Facebook, go to that place instead. Click and drag your mouse from the beginning of the text that you want to copy to the end of the text that you want to copy. You should see the text highlight as you click and drag. Press Ctrl and C (or ⌘ Command and C on a Mac) at the same time. This will copy the selected text. You can also right-click the text and then click Copy... in the drop-down menu that appears. Find a text field (e.g., a comment box or the status box) on Facebook in which you want to paste the text. If you want to paste the text somewhere other than Facebook (e.g., in an email), go to the site, app, or document in which you want to paste the text instead. Doing so will place your mouse cursor in the text field. Make sure that your cursor is in the text field, then press Ctrl+V (or ⌘ Command+V on a Mac) to paste in the text. You should see the copied text appear in the text field.  As with copying, you can also right-click the text field and then click Paste in the drop-down menu. On a Mac, you can click the Edit menu item at the top of the screen and then click Paste in the resulting drop-down menu.

Summary:
Open Facebook. Find something to copy. Select the text. Copy the text. Go to the place where you want to paste the copied text. Click the text field. Paste in the text.