Surface Pen
The Surface Pen is an active stylus and digital pen developed by Microsoft for its series of Surface computing devices. It is designed to showcase the pen computing capabilities of Microsoft's Windows 8/8.1 and Windows 10 operating systems. First generation. The first Surface Pen was introduced in 2012 alongside the Surface Pro, which uses Penabled technology designed by Wacom. It features one physical button on the side to simulate a right-click when the pen comes into contact with the display, as well as an eraser tip at the top of the Pen that removes ink strokes  when it comes into contact with the display. It was bundled with the Surface Pro and Surface Pro 2, but is not compatible with other models. The button on the pen doubles as a magnetic clip which can be used to attach the pen to the Surface charging port (although not while simultaneously charging the device). Although the technology was deprecated with subsequent generations and is now branded as "Pro Pen", it can still be purchased as an accessory for the Surface Pro and Surface Pro 2 as well as other Penabled-compatible devices such as those from Lenovo ThinkPad  lineup. Second generation. Surface Pro 3. A new version of the Surface Pen was launched in 2014 with the Surface Pro 3. Based on technology developed by N-trig (a separate company at the time, though subsequently acquired by Microsoft), the Surface Pro 3 version lacks the eraser tip present in the previous generation; erasing is done by drawing over the ink strokes while holding down one of two physical buttons on the side, above the button used for right-clicking. A third button, located at the back of the pen, sends a Bluetooth signal to a paired Surface PC  which instantly opens OneNote, even when the device is locked (although advanced editing functions are disabled in this case). Unlike the Wacom-powered Surface Pen, it requires two batteries: one AAAA battery for stylus operation, and two size 319 coin cell batteries for the top button. The pen is included with all Surface Pro 3s but is also compatible with and available as an optional accessory for the Surface 3. Unlike the previous pen, this version can be stowed away by sliding it into a self-adhesive felt loop which can be attached to the Surface Type Cover (optional extra ). It is also compatible with all subsequent Surface PCs, which uses the same basic technology. Surface Pro 3 Pen is able to detect 256 levels of pressure on its tip. Model numbers are 3UY-00001 (Silver), 3UY-00012 (Black), 3UY-00021 (Red), 3UY-00030 (Blue). Third generation. Surface Pro 4. With the release of the Surface Pro 4, Microsoft introduced an updated version of the Surface Pen. While using the same technology as the Surface Pro 3 pen, it has only one (non-customizable) button on the side rather than two, and brings back the top-mounted eraser (retaining the button functionality) and also  allows customizing the button (called the "magic button") to perform different actions. The default options are: single-click opens OneNote, double-click takes a screenshot, press-and-hold launches Cortana. This generation saw the return of the magnetic attachment, although this time the pen snaps into place on the opposite side of the Surface device, thereby freeing up the charging port (now called the Surface Connect port). This version of the pen is bundled with the Surface Pro 4, the Surface Book and the Surface Studio; it can also be purchased separately for the Surface Laptop. It is also compatible  with the Surface Pro 3 and Surface 3. The pen of the third generation is able to detect 1024 levels of pressure on its tip. Latency drops to just 45 milliseconds in comparison with Surface Pro 3 Pen. Model numbers are 3XY-00001 (Silver), 3XY-00011 (Black), 3XY-00021 (Dark Blue) and 3XY-00051 (Gold). A set of 4 interchangeable pen tips were included with this pen, but only made available as an option (Model RJ3-00003) for the fourth generation pen. The tips are marked using the same nomenclature used for pencil hardness 2H, H, HB, B. Surface Hub. The Surface Hub, released  in June 2015, ships with a pair of digital pens that employ technology similar to the Surface Pen for PCs. Holstered to each side of the device, they have eraser tips but no extra buttons. They integrate with the built-in Whiteboard app and, unlike the Surface Pen, can both be used for simultaneously inking by multiple users. Fourth generation. Surface Pro (2017). With the release of the Surface Pro 5th gen, Microsoft introduced an updated version of the Surface Pen. Unlike previous generations of the Surface Pen, this version of the pen is sold separately at a higher price  of $99. It is also compatible with Surface 3, Surface Pro 3, Surface Pro 4, Surface Pro 6, Surface Pro 7, Surface Pro X, Surface Go, Surface Go 2, Surface Studio, Surface Studio 2, Surface Book, Surface Book 2, Surface Book 3, Surface Laptop, Surface Laptop 2 and Surface Laptop 3. The new Surface Pen is able to detect 4096 levels of pressure and has 1024 levels of tilt sensitivity, which was not available in previous generations. It has 21 milliseconds of latency, making it "the fastest digital pen on the planet” at the time of release, according to  Microsoft. Model numbers are: