This is a compact x86 PC in a metal enclosure, as shown between two cordless phones in the picture.  Note that the keyboards and mouse in the picture are not the ones supplied with this machine.  The included keyboard was warped, but it and the mouse were good enough to get started.  Because the machine itself is outstanding, I'm not taking points off for the keyboard and mouse.A small fan keeps the chassis cool with very little noise, and the external power supply (input 110 to 240 volts, 50/60 Hz) is convection cooled.  When I first turned on the machine, it immediately upgraded from Win 10.x to the latest Windows 11.  Since I have another machine which runs Windows, I installed Ubuntu Linux on this one.  Performance in Windows was good, and performance in Linux is excellent.  With 8 gigabytes of memory, swapping is minimal.There are a total of 5 USB ports and a network jack, so even with  the  mouse and keyboard plugged in there is one more available on the back panel and two more on the front panel.In addition to a VGA output the machine has a DisplayPort output, so two monitors can be used.  Since very few monitors have a DisplayPort input, an Amazon Basics adapter to convert a DisplayPort output to HDMI is available separately.  Or if you happen to have a compatible monitor, there is also a DisplayPort to DisplayPort cable.  The DisplayPort to HDMI adapter works beautifully.  Since Display Port doesn’t support audio, stereo input and output mini-phone plugs are provided on the front panel of the ThinkCentre.A combined WiFi and Bluetooth adapter (USB) is  included.  Despite its small size and built-in antenna, it works well for reasonably strong signals.  It was able to detect a nearby Bluetooth device, and easily connected to my 2.5 gHz WiFi.  However, it does not support 5 gHz WiFi.All in all, this this is a great machine for almost any use except perhaps heavy-duty video gaming, and at a good price.  With its all-metal construction and good cooling, I expect it to last a long time.One quirk that may surprise users not accustomed to the ThinkCentre is its wakeup feature.  When the feature is enabled, any input such as keyboard, mouse, or network may turn the machine back on from its low-power standby state.  While that is great for some uses, it can be annoying if you expect the machine to remain off after shutdown.  On my machine, the machine appeared to be waking up due to the LAN, since it didn’t happen when LAN was unplugged.  WiFi (if equipped) could be another potential cause.  Any unwanted wakeup signals can be disabled in the Wakeup Menu, as described in various articles or videos about Lenovo computers on the web. I chose to leave only the power button enabled as a wakeup source, but not LAN, keyboard or mouse (among others).