Pistol Sights – Irons
Almost all handguns you can buy now have some variation on the venerable “post and notch” iron sight. The front sight is the “post”, sticking up from the middle of the muzzle end of your slide, and the rear sights are the “notch”, providing you with reference points at the back end of the slide towards you. The fundamental of shooting known as the sight picture is the process of lining up and maintaining equal height of the front and rear sights, with equal light on either side of the front sight inside the rear notch.

Equal light; equal height – a perfect sight picture
While you read, you should remember that no matter what your dream gun comes with or what the gun you already have has installed, iron sights are one of the easiest things to change. Installation can be done quickly and inexpensively by your local gunsmith or if you’re brave, is one of the easier and safer home gunsmithing projects you can take on.
The most common variety of iron sights are probably the “three-dot” style, where there is a dot on the front sight and dots on each post of the notch making up the rear sight. The dots can be plain paint, glow-in-the-dark tritium vials, fiber optic, or a combination, and they can be different sizes. Three-dot sights provide a lot of visual input, but it can be tempting to line up the dots instead of the actual blades of the sights.

The glow-in-the-dark night sights on my carry pistol are three-dot style

Stock Glock sights on the left; a “bar and dot” sight on a Kahr pistol on the right
With sights that have painted dots, you can quickly and easily modify them by just drawing some black marker over the rear dots. You can also experiment in the short term with tiny pieces of black tape.

Competition sights with a fiber optic in the front sight post, and three-dot sights modified at home to reduce rear dots
And while standard post and notch iron front sights are pretty much just rectangles with or without a dot in them, there are many more options for the rear. The notch may have a flat bottom or a more U-shaped curve. The entire sight could be rectangular or have curved outer corners. They might be adjustable through tiny exterior screws or fixed.

Adjustable, rectangular rears on the left; fixed and curvier rears on the right
A well written article. I enjoyed it and it is definitely great for new shooters.
For myself, from personal experience everywhere from Iraq to numerous CONUS locations, most iron sights work pretty well. I do have night sights on one of my G21s and a colored Lucite front sight on a 22/45 I used a lot for indoor speed shooting competition. To be honest though, in a close encounter shooter situation you pretty much get the front sight on the target and go from there. Most factory sights work just fine for this, whether I’m using my Jericho, Ruger AP or a Glock.
I tried a diamond version of the Hex sight and didn’t like it. It covered up too much of the target and was a big lump on the back of my pistol. I currently have Speed sights on my pistol with the diamond shape dots. I rally like these. They are easy and quick to pick up and you can get more precise sight alignment. They are working for me so far. As long as you are not outside in the sun, laser sights are the best but have limited application because they are hard to see in bright light conditions.