Difference between "notebook" and "laptop"

Definition of Notebook :

a small, lightweight laptop computer.

Definition of Laptop :

a portable, usually battery-powered microcomputer small enough to rest on the user's lap.

In this case, a notebook is defined as a laptop, so does "notebook" = "laptop"?

The laptop was originally designed to be similar to a desktop, but be small and light enough that it could be used while sitting in your lap. For this reason, years ago, you would find that a laptop had more features than notebooks did, but the tradeoff was being larger and heavier than a notebook. This is because the notebook style of portable computers was for mobility, not just portability. To be a more mobile device, the notebook was a thinner design and it weighed less than the laptop, simply because it didn't come packed with features and multiple devices and drives.

Years ago, notebook computers would have a smaller display than a laptop, fewer internal drives (hard drive, floppy or CD-ROM - depending on the year manufactured), and the sound, modem, and such would be integrated - not separate upgradable hardware devices. Laptops were considered to be desktop replacements; portable computers with features, functions, and options comparable to your desktop computer.

So while there technically is a difference between the two -- and that is the size and weight of the device (which in turn impacts the system's features) -- today there is even less of a difference between the two since technology advancements means that most common computer devices and peripherals are much smaller now.

Example: When NEC released its UltraLite Notebook in 1989, a portable PC that many attribute to being the first notebook computer, it contained a CPU, RAM, ROM, 2MB solid state memory storage, a built-in modem and one RS-232C port. It weighed 5 pounds. The laptops from around this same time frame, such as the Compaq SLT/286, would typically have a CPU, memory, hard drive, floppy drive, VGA display and could weigh up to 12 or 14 pounds. The laptops could be two to three times the thickness of the notebook.

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Alternatively, you can click here for a more organized table of difference between notebooks and laptops.