Photography terminology (for newbies)

Here is my attempt to list the basic photography terminology (a photography vocabulary you will need to master before you press the trigger). Note that this list explains the items in a "for dummies" style. When I started learning about shooting, I had to search for the expressions mentioned by other photographers every now and then... and list like this would have helped me a lot.
If you think of an expression I missed, please add a comment with the suggested term. I will be happy to add it to the list.

• hot shoe -- the thing on top of your camera, where you would slide the flash. It has metal parts that touch another metal parts at the bottom of the flash which will allow your camera to close an electrical circuit that triggers the flash
  
• exposure -- amount of light that hits the camera sensor while the shutter is opened
  
• shutter -- a thingie that is in front of the image sensor that opens and closes, allowing the light from the lens to hit the camera image sensor
  
• shutter speed -- how long is the shutter opened (should be long enough to have correct exposure -- enough light should get in to paint a nice picture onto the image sensor)
  
• aperture -- how wide your shutter opens when it opens, determines how wide is the beam of light coming from lens to the camera sensor
• F-number -- a measure of how wide is your aperture, a measure of a "lens speed" (smaller F-number means that the shutter is more opened and more light comes in)
  
• aperture priority -- a setting on a camera that allows you to specify a fixed aperture (and let the camera adjust all other variables to make a correct exposure)
  
• ISO -- a measure of sensitivity of light (use higher ISO number in darker room, low ISO outside in the daylight)
  
• strobe -- flash, speedlight, a thing that emits light
  
• composition -- an arrangement of elements that you are taking a picture of
  
• lens -- a photographic objective -- a device that contains optical lens (or lenses) and other mechanics allowing to focus, to zoom, all while projecting the not-distorted image at the image sensor
  
• focal length -- a measure of how strongly the optical system focuses or defocuses light; the distance in air from the lens or mirror's principal plane to the focus
• focus -- a point of convergence of light
• auto-focus -- a feature of an optical system that allows you to obtain a correct focus on a subject
• light stand -- see the below photo
• umbrella adapter -- click on the below photo and see the notes (picture is worth a thousand words)
• wireless flash triggers -- a.k.a. "pocket wizards", these are devices that tell your strobes to fire when the shutter is pressed on the camera. You mount one trigger on the hot shoe of your camera and another below your flash (flash mounts on a hot shoe of the second trigger). See photo below.
• bokeh -- blurry, fuzzy background, see examples