Laptops were not the first "portable computers." Before laptops, a "portable computer" was about the size of a suitcase, weighed 15 kg or more, and did not have batteries. They had to be plugged into a wall outlet. Famous models included the Osborne I and the Compaq.

The late 1980s. Maybe 1986-1990. IBM introduced its first laptop in 1986, the Convertible. It had 256K = 0.256 Mb = 0.000256 Gb of RAM, two diskettes, and no hard drive. It did poorly because it wasn't fully compatible with their desktop PC. I remember my boss buying a huge laptop in 1990, because she needed something for product demonstrations. It had to have an Intel 386 processor--i.e. fully equivalent to a high-end desktop. It had a screen that folded over the keyboard, but that was only the front end. It weighed around 15 Kg. But at any rate, but 1990 you could get a wide range of models including very capable ones that were fully comparable to desktops. The first laptop in our household was a Toshiba that my wife bought in 1990 or 1991. "Of course" none of these had color screens. I'm not even sure they had graphics, they might have been 24x80 only. I remember another laptop from 1991. Again, my boss needed it for a product demonstrations. It had to be color. At the time there was only one model available. It it was made by Sharp, it cost USD $4,000. Unbelievably it had only 15 minutes of battery life.