File menu
Template Chooser — Open the template chooser, where you can pick which template you'd like to use for a new document.
Open — Browse for a document to open. You can open any OmniGraffle document, or a file in one of the formats OmniGraffle knows how to import.
Open Recent — Open a document you've recently worked on. Choose Clear Menu to remove the list of recent documents, so no one knows you've been working on "Surprise Party Invitation.graffle".
Close — Close the frontmost window you have open. If you have unsaved changes, you are prompted to save or discard them.
Save — Write all of your hard work in the frontmost document onto the disk for safekeeping. If you have already saved the document once, the new version replaces the old one. If it's the first time you're saving this document, you are prompted to browse to a location on the disk and enter a file name.
Save As — Write the frontmost document to the disk, but with a new name. This means you get a new, differently-named version of the file, and the existing old version of the file remains just how it was.
Save All — Write all of your hard work, in all of the open documents, onto the disk, all at once.
Revert to Saved — When revisions don't really work out like you had planned, choose this to go back to the version of the file that's on the disk; it's kind of like a mass-Undo. If you open a file that had some changes in an automatic backup, you can choose this command to go back to the last explicitly saved version.
Place Image — Browse for an image file; a shape containing the image is created on the canvas at the last place you clicked with the Selection tool.
Export — This creates a new file, in a file type of your choice, from some portion of the data in your OmniGraffle document. Exported files are approximations of the OmniGraffle document in a different format, not perfect replicas. Check the exporting section for more information.
Page Setup — Show the standard Mac OS X Page Setup sheet. This sheet contains several panes of settings for how to represent your document on pages.
Print — Show the standard Mac OS X Print sheet. In addition to the settings in Page Setup, you have a lot of printing-specific options you can set here.
Print Canvas(es) — Show the Print sheet, but only include the selected canvases.