Domain forwarding is a service that is available with your domain registration. It allows you to redirect visitors to another website (that you own) when they type your domain name in the browser address field. It can also mask the real destination by always displaying your domain in the browser address field.
Example: When a user types www.example.com in their address bar, it shows the content from www.webhost.com/~username/
Email forwarding is a service that is available with your domain registration. It allows you to redirect email from an address associated with your domain to another email address. The forwarded mail is filtered for spam.
Example: Email sent to email@example.com is automatically forwarded to firstname.lastname@example.org