A size comparison of 3.5" and 2.5" hard disk drives

• Removable media drives – A DVD/CD reader/writer drive is typically standard. CD drives are becoming rare, while Blu-Ray is becoming more common on notebooks^[37]. Many ultraportables and netbooks either move the removable media drive into the docking station or exclude it altogether.

• Internal storage – Laptop Hard disks are physically smaller—2.5 inch (60 mm) or 1.8 inch (46 mm) —compared to desktop 3.5 inch (90 mm) drives. Some newer laptops (usually ultraportables) employ more expensive, but faster, lighter and power-efficient Flash memory-based SSDs instead. Currently, 250 to 320 GB sizes are common for laptop hard disks (64 to 128 GB for SSDs).

• Input – A pointing stick, touchpad or both are used to control the position of the cursor on the screen, and an integrated keyboard is used for typing. External keyboard and mouse may be connected using USB or PS/2 (if present).

• Ports – several USB ports, an external monitor port (VGA or DVI), audio in/out, and an Ethernet network port are found on most laptops. Less common are legacy ports such as a PS/2 keyboard/mouse port, serial port or a parallel port. S-video or composite video ports are more common on consumer-oriented notebooks.