The terms laptop and notebook are often used interchangeably to refer to each mobile computer, and not everyone agrees on what the difference is between the two terms, or if there are others. The conventional difference is that notebooks are so named to differentiate the class of phones by being ultra-light, ultra-thin, and highly portable, compared to the original laptops which are relatively complicated. With advances in mobile technology, laptops have evolved into what were previously considered notebooks, explaining why the terms have become interchangeable.
Today's ultra-light mobile computers that maintain a full operating system and functionality are known as subnotebooks or ultraportables. Some models do not include a CD / DVD player, and they can be used with an optional docking station to enhance features.
The specifications for which a notebook qualifies to fall into this category can be somewhat arbitrary but in general, the machine will be significantly smaller and lighter than the average laptop. The high-quality, power-saving components also result in longer time between battery charges. These favorable attributes make ultraportables two to three times more expensive than their larger, heavier counterparts.
Mid-range mobile computers typically weigh close to 2.72 kg with a 15-17 inch (approx. 38-43 cm) screen measured diagonally. The keyboard is spacious, and the included DVD player may have Blu-ray ™ capability. USB and FireWire ports, built-in WiFi®, Ethernet, Bluetooth, webcam, and a flash card reader have become standard in all of them. Computers in this class have essentially become desktop replacements, blurring yet another distinction previously made to classifying very heavy desktop phone models, although some laptops are heavier in size.
Netbooks (versus notebooks) are the smallest and most portable class, providing an inexpensive alternative to online surfing and basic applications. They don't come with a CD / DVD drive, but they generally include built-in WiFi®, Ethernet, USB port, flash card reader, webcam, and headphone and microphone jacks. Most have a screen appearance of 6 to 10 inches (15.24-25.40 cm).