based on an article by kccloud solutions
PROS: With the Insert >> Image method, you can quickly and easily add an image to your site. This is a one-step method that allows you to upload, select and embed the image all in one location.
CONS: Potentially, images inserted with the Insert >> Image may be duplicates of images already uploaded. This redundancy eats into the space allocation.
Recommended? Quick and easy to understand for newcomers - Yes.
CONS: As the heading for this section explains, files attached here are page-specific. By this, I mean that these files will not show up when browsing for files (images) to embed in other pages of your site. They are, however available to use on other pages if you know the URL.
Recommended? Yes. It is just as easy to manage as a file cabinet page, and you have the ability to completely hide the list of attachments, whereas with a file cabinet page, you do not.
Another reason to make full use of page-specific attachments is the addition of a global attachments management feature in the July 2009 release of Google Sites. With this feature, site administrators can add, delete and move files across the entire site from a single location: More Actions >> Manage Site >> Attachments. For more information, see the Sites Guide - Manage Site article.
PROS: A File Cabinet page can be used as a central management point for a group of attached files. It is easily accessible, and can be accessed with little effort.
CONS: File Cabinet pages cannot be hidden from view. Even if the page is not displayed in your site's navigation menu, it will appear in the sitemap, which is accessible to all site visitors.
Recommended? Yes. A File Cabinet page is useful for uploading and keeping track of revision history for attached files. It is also good for organizing files through the available folder structure. (Although the folder management features are somewhat lacking at this time, they can be quite valuable for even the most basic file organization and management requirements.)
See also how to... Insert an image from a File Cabinet page into a content page
As noted above, Google added a global Attachments feature to Sites with the July 2009 release. This addition provides robust control over all site attachments from a single interface.
PROS: The global Attachments feature allows you to upload, move, rename and delete any and all files that have been uploaded and attached to your site, all from a single location.
CONS: Due to the series of clicks that must be made in order to access the global Attachments feature, it is not ideal for managing files on a one-off basis.
Recommended? Yes. When you have a need to move an attached file from one location to another (within the same site), this is a quick and painless way to go. It is also a great interface for performing site cleanup by deleting multiple attachments at once.
To remove files from a File Cabinet page, log into your site and perform the following steps:
To remove files from a page-specific Attachments section, log into your site and perform the following step:
To remove files using the global Attachments feature, perform the following steps:
Note: This method is the only way to remove images that have been added to a site via the Insert >> Image menu option.
With the Insert >> Image method, you can also replace an existing image by uploading another image with the exact same name. The only thing you will not see is the revision history that the other two methods offer.