Weight and bay design: Notebooks weigh from a 17-pound desktop replacements to 8 – 10-pound all-in-one models with built-in optical drive, to 3-pound portables relying on external drives. Many laptops offer the optical drive as a modular device, and you can swap it for a second hard drive.

Communications: Few notebooks are equipped with a full set of legacy ports. Serial ports are rare, most have parallel port and one PC Card slot. A majority of notebooks include a FireWire port for connecting external drive, MP3 player, or digital-video camcorder.

Built-in ethernet are now standard on all portables, with models carrying gigabit ethernet.