Transfering files is easy with Yahoo! Messenger. There are several ways to do it:

• When you're in an IM conversation, you can simply drag-and-drop one or more files right into the IM window. The other person will be invited to "Save" the file or "Decline" the file transfer. Either way, you will be notified of their decision, and if they choose to accept the file transfer, your IM window will show the progress of the file transfer.
• During an IM conversation, you can click the "Send File" button or select the "Send a File" command on the "Actions" menu.
• You can drag-and-drop a file onto a contact in your Messenger List, even when you are not currently IMing that person.

If the files you drag-and-drop are all image files (like JPEG or BMP files), an inline notification will give you the option of starting a Photo Sharing session. If you choose this option, your friend will be invited to photo sharing. If your friend accepts, your image files will appear in a side panel, and you will have access to additional features that make photo sharing more fun.

There is no limit to the size of files you can transfer, as long as neither you nor your friend are behind a firewall that prohibits peer-to-peer transfers. In that case, the file will be sent through Yahoo! servers, and file size is limited to 100MB.

In a single file transfer, you can transfer an unlimited number of files to anyone on your Messenger List. The number of files that can be transferred at one time during a conversation with someone who is not on your Messenger List, however, will be limited.