Two Internet Connections To One Computer

Is it possible to have two internet connections for one desktop? I know many of you may say yes it is which I know but the two connection would be wired connections, which I would like both to be connected to my desktop, and I can then choose which connection to connect to and switch whenever the requirement. If any routers are required please provide details for that too.
Yes you can use two different connections with one computer. You can use a wired and a mobile connection and also use two mobile connections as well as two wired connections.
Yes you can use two different broadband connections with one computer, just switch the connection when you want to use the other one.