Ports are one method by which tablets communicate with other devices, and charge, with others being such as WiFi, the less common Bluetooth and the extremely rare Near Field Communication.
The main port that the nabi DreamTab has is its nabi Connector port. This is an unusual port, as most tablets come with a standard micro USB port instead. The nabi Connector can do the same things as a micro USB port, including connect to other devices and charge the tablet, but it also functions as an HDMI port. The downside of this custom port is that it needs a custom cable too – should the cable develop a fault, or be damaged, it cannot be simply swapped with a standard cable but requires a special one.
Other ports are the micro SD card slot and a 3.5 mm headphone jack. The nabi also has two cameras and a built-in microphone.