If you're left-handed, today is your day. It's International Left Handers Day, a holiday promoted by the UK-based Left Handers Club. You're also in good company: Bill Gates, Oprah Winfrey, and Barack Obama are all left-handed, among many other luminaries. Still, you're very much in the minority--statistics vary, but somewhere between 75 and 90 percent of the world's humans are right-handed. 

It seems that no one truly understands left-handedness. The theory is that the majority of us are right-handed because language is generally controlled by the left side of the brain, which uses fine motor skills to enable you to speak. Since you also need fine motor skills in your dominant hand, it makes sense for the same brain hemisphere that controls language to also control that hand. (The left hemisphere of the brain controls the right side of your body, and vice versa.) Left-handed people, then, either have their right hemispheres controlling language and fine motor skills, or they have a more variable set of controls within their brains than the rest of us. 

But there seems to be more speculation than established fact about left-handedness. A blinding array of studies have linked a dominant left hand to pre-natal events, a greater risk of Parkinson's disease or multiple sclerosis, higher earnings, lower earnings, and a talent for math or music, among many, many other things. 

But those of you who are left-handed know there are a lot of everyday activities that present special challenges for you, while those of us who are right-handed barely give them a thought:

1. Using a faucet.

First of all, the most commonly used cold water is always on the right. Second, you turn it on by turning the tap counter-clockwise, a natural direction for the right-handed. If you're left handed, it's very awkward.

2. Using a subway turnstile.

When I was growing up, a left-hander once complained to me about the difficulty of trying to get a token into the slot in the New York City subway. That was a fine-motor-skills job for sure, so she had to reach across her body with her left hand to do it, usually with a line of people waiting impatiently behind her. These days, you swipe a card instead, which is only slightly less challenging.

3. Eating with friends in a restaurant.

I have a left-handed friend who always requests an outside seat with her left arm free in a restaurant, especially when sitting in a booth. Because if she sits to the right of a right-handed dining companion, the two of them will wind up elbowing each other as they try to eat their meals.

4. Writing.

In languages such as English that are written left to write, left-handers have an awkward time because their hands travel over what they've just written and are liable to smear the ink. Of course, these days most of us do most of our writing on a keyboard which levels the playing field considerably. But if that keyboard has a built-in trackball or touchpad on the right--well that's a whole other problem.

5. Cutting stuff. 

Scissors are very much designed for right-handed people, with a large opening for the fingers and a smaller round one for the thumb. They're also designed to cut at that angle, so they won't work well for left-handers who turn them upside down.

Then there are serrated knives. I never knew these were designed for right-handed people, but apparently the serrations are designed to give you a straighter cut when used in the right hand. They'll give you a crooked cut when used in the left hand.

6. Opening wine.

Given all the challenges of left-handedness, you surely need a drink. But corkscrews, like water taps, are designed to be turned easily by right-handed people and are awkward for left-handed people to turn. Even screw tops are designed for righties.

But to compensate in some small way for all the challenges of left-handedness, Oreo has come out with a special left-handed cookie package in celebration of today. The cookies themselves, of course, are neither left-handed nor right-handed, but the package is designed to be torn open from right to left instead of left to right as usual. Enjoy!