Laptops Are Actually Clamshell-Style Portable Computers
While we think of them as standard devices, laptops are historically defined as portable computers because every core component is physically fused into a single unit. Unlike desktop PCs, these machines bundle your screen, keyboard, and power supply into one moving piece.
The term portable computer once referred to heavy machines that look nothing like today's sleek laptops. Early designs were often called luggables because they weighed as much as a small suitcase. Over time, engineering advances allowed manufacturers to shrink these components into the compact, folding clamshell shape we use now. Interestingly, the industry strictly separates these foldables from tablets and phones, which are officially classified as mobile devices.
Source: Portable computer