But it is fraught with peril. Attachments can include viruses.
Application software is needed.
Attachments take longer to download . Attachments may or may not decode properly. People receiving your attachment will not be able to read it unless they have software on their computer that can read your file. Attachments created with new versions of software often can't be read by persons who have earlier versions of the same software. An attachment created in WORD 2000, for example, won't open for someone who has version 5.1 of the same WORD software.