<P> The majority of portable computer manufacturers today (including HP, Dell, and Samsung) currently place the Fn key between the left Control key and the left Windows key, making it the second key from the left on the bottom row of the keyboard . This usually means that the Control key is reduced in size, but allows it to remain in the lowest - left position on the keyboard . </P> <P> Conversely, Lenovo currently arrange keyboards on their ThinkPad computers with the Fn key as the lowest - left, making Control the second - from - left on the bottom row . This arrangement is currently unique to ThinkPads amongst all laptops shipped with Windows, but it is one that has been in place since the modern ThinkPad product line was introduced by IBM in 1992 . IBM designers rationalised that since the Fn key was used to control features that in some cases had no other physical or software controls (for example, the ThinkLight keyboard - illumination lamp, which is switched only by the Fn + PgUp keys), the Fn key should have the more prominent position on the keyboard . Notably, IBM did not include Windows keys on any of their keyboards until 2006, which meant that though the left Control key was displaced by the Fn key, neither it nor the left Alt key needed to be made smaller . The inclusion of Windows keys on ThinkPad models from mid-2006 onwards was achieved mainly by shrinking the left Alt key, which means that ThinkPad keyboards now generally have larger left Control keys than those of many other manufacturers, and are unique in preserving on laptops the Control, Windows, and Alt key arrangement used on most desktop keyboards . Many laptops place the Fn key at a less convenient position (and with a smaller size) within the top row of functions keys F1 to F12 and other "multimedia" or manufacturer - specific device / power control key . </P> <P> Apple also place the Fn key at the bottom left of the keyboard, displacing and shrinking the left Control key, though this is less controversial as macOS, the main operating system for most Apple laptops, is much less reliant on the Control key for shortcuts and modifiers than Windows or Unix - like operating systems . </P> <P> This inconsistency between manufacturers, and the overall issue of Control key shrinkage, has long been a point of contention between laptop purchasers and users, which is aggravated by the fact that on most keyboards the Fn key is mapped at the hardware level and so cannot be remapped (that is, reconfigured or virtually "moved") at the OS level . Lenovo, however, have since circa 2011 allowed users to reverse the Fn and left Control key arrangement via a BIOS setting . </P>

Which is the fn key on a mac