Share PDF allows you to email or copy a PDF with our without annotations (drawings) to another application or to anothe iPad via AirDrop.
To email or send a PDF to another application that can handle PDF files, set the With Annotations option on or off then press Share… A list of compatible applications will appear. Press an application icon to send the PDF to that application. If you are using iOS7, you can also AirDrop the file to another iPad or iPhone if both devices are AirDrop capable. Select the Mail application to email the file. If you are connected to Dropbox, you can also upload the current file to a Dropbox folder.