Copying and pasting eliminates the need to retype text.
You can copy from and paste text into:
Text fields
Terminal emulator windows
Text Editor windows
Mailer Compose windows
You can also copy text from a Mailer message view and a Help Viewer window and paste it into Text Editor, terminal emulator, and Mailer Compose windows.
Move the pointer to the start of the text to be pasted.
Drag to the end of the text to be pasted, then release the mouse button, leaving the text highlighted.