Over the last few decades, software applications evolved from character mode terminal applications , to desktop applications, to client/server (network enabled desktop) applications, and now to Web applications. Client/server applications brought distributed computing to reality first. One of the key differentiators for these client/server applications is connectivity – they connected to the server over a network and received and sent data over full duplex network connections and had access to realtime or near realtime data, depending on the network latency. The server could push a message to the client anytime.