Cloud-based services (Dropbox or Wetransfer)
Your files are uploaded to a random server and typically replicated on other servers depending on the companies backup policy. A web link is then used to retrieve the uploaded files. Even after files have transferred, cloud-based services will continue to host your files on their servers for an unknown period. Cloud services share bandwidth amongst users which can lead to slow download speeds as users are uploading/downloading from the same provider.
Depending on your email provider, the maximum size of Email attachments is 10-25MB. Sent files are uploaded to the provider's servers and saved at multiple points. The process of sending many emails to bypass the maximum attachment size, become a confusing and cumbersome process.
File Transfer Protocol(FTP) technology
Files are uploaded to a central server and FTP clients are configured to exchange files via the FTP server. Ports have to be opened, accounts created, and security closely monitored.
Peer to peer technology (BitTorrent)
Many copies of the file are available on multiple computers and pieces are downloaded from multiple parties to assemble the final file on the destination.