The D-Terminals are usually confused with being like a Digivice. In actuality D-Terminals are popular and commercially available to the public. D-Terminals are like palm pilots; they are small computers used to carry out small electronic tasks, such as email.
Each DigiDestined owns a D-Terminal, so that they can communicate with each other. For the new DigiDestined who received DigiEggs, the D-Terminals are able to hold their DigiEggs.