Having a twitchy eye is a fairly common annoyance, and one that you are going to notice far more than anyone else does. It might feel like your eye is vibrating in an alarming way, making you look crazed to anyone who looks your way, but it always feels worse than it looks. It has to be pretty bad for people other than you to notice, but luckily, it's perfectly benign.
Far from a serious problem, eye twitches are instead caused by other deficiencies that you can set right. While they might be extremely irritating, you could think of them as the body's way of signalling something is a little off. Many associate eye twitching with anger or annoyance, but it's not connected to any emotion really. Instead, they are usually a symptom of something else.
The primary reasons why you could be distracted by random pulses in and around your eye are tiredness and stress. If you're leading a rushed, sleepless lifestyle, battling with insomnia then becoming buried in responsibilities at work - this could be your body letting you know you should slow things down a little and get some rest.
Another possible cause could be eye strain - either because you've spent too long without your glasses, or you need glasses but just don't know it yet. If you're leading a calm life with plenty of good sleep to go around, and are wearing your glasses all the time, consistent twitching may mean you need to go for an eye exam and change your prescription.
In addition to this, twitching can also be caused by excessive use of your computer and smartphone. Staring at a bright screen for too long, especially a small one, can exhaust your eye muscles. Doing this before you go to sleep in bed can negatively affect your sleep as well, so it's probably worth cutting down on your usage anyway. Or, if you use computers a lot for work, you can always get special computer eyeglasses to take the strain off your eyes.
Some less common causes can be too much caffeine or alcohol, or dry eyes - in which case you can use eye drops to solve the issue. Two more possible answers are nutritional imbalance or allergies, but both of these are not confirmed to have a direct link. In some studies, it has been speculated that an unhealthy diet with too little magnesium could lead to twitching, and the overproduction of histamine (which is released during allergic reactions).
Seeing as I don't get enough sleep, have various allergies, survive on coffee and live in a stressful busy city, it's not too surprising that I get twitches in my eyes from time to time. For anyone living in the hustle and bustle of a city and working in an office each day, eye twitching is a likely occurrence, but it isn't really harmful.
Just be careful it doesn't look like you're creepily winking at strangers.