Netbooks are very low cost portable laptop computers with screens that are under 30 cm in size and usually feature low cost CPU's, small batteries and other hardware limitations, such as limited amounts of memory and little if any expansion potential. These should not be confused with sub-compact notebooks or subnotebooks but these are full powered laptop PC's in a small form factor.
Netbooks were popular amongst eComStation users as the bulk of them sported old Intel or Via chipsets that had full support on 1.x versions of the system and the limited memory and storage available hampered OS/2 much less than it did Microsoft Windows or Linux.
While there had been attempts to create a market around low cost portables prior to this, netbooks came into their own in 2007 when Asus released the Eee PC which was a slow mini-laptop with only 2 to 4GB of SSD storage and an LINUX based operating system made available in two versions with a 7" (18cm) and a 10.1 (25.7 cm) screens but otherwise similarly specified. It created quite a stir in the market and it initially sold well, saled dropped very rapidly after a few weeks and ASUS countered by introducing a version that used a new low cost version of Microsoft Windows XP that was made specifically for the device that had limitations in the number of programs that could run at once and could only address 1GB of memory and gradually withdrew the LINUX version.
Netbooks had their heyday around 2009 but at the time all makers of PC compatible notebooks had at the least one netbook model on offer, but after that the sudden drop in prices of 15" screens and the rise in the popularity of tablets they dropped rapidly in popularity especially after 2012, by 2016 there were only a few models on the market that fitted the description.