# Open a PDF

You can open a PDF from within the Reader application, from the desktop, or from within certain other applications.

### Open a PDF in the application

Start Reader and do one of the following:

- Choose File > Open, or click the Open button in the toolbar. In the Open dialog box, select one or more filenames, and click Open. PDF documents usually have the extension .pdf.

- (Windows/UNIX) Choose File > [a previously opened PDF].

- (Mac OS) Choose File > Open Recent File > [a previously opened PDF].

If more than one document is open, you can switch between documents by choosing the document name from the Window menu. In Windows, the application places a button for each open document on the Windows taskbar. You can click this button to move between open documents.

### Open a PDF from the desktop or within another application

Do one of the following:

- To open a PDF attached to an email message, open the message, either by double-clicking the PDF icon or right-clicking/Control-clicking and choosing Open.

- To open a PDF linked to an open web page, click the PDF file link. The PDF usually opens in the web browser. In UNIX, you can open the PDF in Reader or save it to the desktop.

- Double-click the PDF File icon in your file system.

  Note: In Mac OS, you may not be able to open a PDF created in Windows by double-clicking the icon. Instead, choose File > Open With > Reader.