New terms are invented each time a new class of small computers becomes popular and/or somewhat standardized, to distinguish them from the previous ubiquitous type.

• "Portable computer" was the original term in the 1970s and 1980s covering machines like the Oborne One, these were retro-named "luggable" later on to make fun of their unwieldy size.
• "Laptop" took off in the late 1980s to distinguish the first flat, fold-open computers that didn't require a desk.
• "Notebook" took off in the 1990s to emphasize machines smaller and lighter than the laptops more common up to that time.
• "Netbook" took off a few years ago to describe very small laptops with wi-fi internet but without legacy features like disk drives.

Of these terms, all have levelled off in their usage except for "laptop" which seems to me the generic term for now.

New terms are invented each time a new class of small computers becomes popular and/or somewhat standardized, to distinguish them from the previous ubiquitous type.

• "Portable computer" was the original term in the 1970s and 1980s covering machines like the Oborne One, these were retro-named "luggable" later on to make fun of their unwieldy size.
• "Laptop" took off in the late 1980s to distinguish the first flat, fold-open computers that didn't require a desk.
• "Notebook" took off in the 1990s to emphasize machines smaller and lighter than the laptops more common up to that time.
• "Netbook" took off a few years ago to describe very small laptops with wi-fi internet but without legacy features like disk drives.

Of these terms, all have levelled off in their usage except for "laptop" which seems to me the generic term for now.

Here's a useful visualization thanks to Google Ngram Viewer: