A portable computer includes a portable computer body having an upper surface, a lower surface and a lower front edge thereof. In particular, a trader can configure the trading application to automatically send orders for preset quantities at price levels with queues falling below a user-defined threshold. The electrode terminals aligned along the substrate edges are coated, at least in their portions close to the substrate edge, with a protection film having a thickness of several tens micrometers or less. The current path is configured to pass a current when the switch is off, and the switch is configured to pass the current when turned on.