Minimizing File Size
Once you've saved your document, Acrobat has a feature that looks through the PDF file and makes changes to minimize the size of the file. This process entails rearranging the internal structure of the document and storing repeated graphics in a more efficient form.
You should always do this with PDF files you're going to distribute electronically. It often makes little difference, but sometimes it results in an impressive reduction in file size.
To reduce the size of a PDF file
With your document open, select Document > Reduce File Size.
The Reduce File Size dialog box opens (Figure 3.9).
Figure 3.9 The Reduce File Size dialog box lets you choose the earliest version of Acrobat with which your file must be compatible.
In the pop-up menu, choose the earliest version of Acrobat with which your file must remain compatible (Figure 3.10).
Figure 3.10 Pick the earliest version of Acrobat that your readers may own.
Choosing higher versions of Acrobat may make the resulting file smaller, but it will also prevent people from reading the file if they haven't recently upgraded their version of Acrobat. The default value is "Retain existing"; this means the new file should have the same Acrobat compatibility as the original.
Click OK.
The Save As dialog box opens.
Provide a name for the new, slimmed-down file, and click OK.
Acrobat works for a while and then saves the reduced file with the new name.