Bluetooth is a proprietary open wireless technology standard for exchanging data over short distances (using short-wavelength radio transmissions in the ISM band from 2400–2480 MHz) from fixed and mobile devices, creating personal area networks (PANs) with high levels of security. Y DisplayPort 1 HP ProBook 6555b, 2.3 GHz, 15.6", 1366 x 768 pixels, 2 GB, 250 GB, Windows 7 Professional HP ProBook 6555b. Processor model: P520, Processor frequency: 2.3 GHz. Display diagonal: 15.6", Display resolution: 1366 x 768 pixels. Internal memory: 2 GB. Total storage capacity: 250 GB, Optical drive type: DVD Super Multi DL. Discrete graphics card model: AMD Radeon HD 4250. Operating system installed: Windows 7 Professional. Product color: Silver. Weight: 5.53 lbs (2.51 kg)