Carpooling is a popular alternative in America for getting to work or school. People “carpool” when they share a car with one or more people. Carpooling aims to reduce travel expenses, traffic jams, and air pollution. When carpooling, people use private cars instead of commercial vehicles like buses. Most people share their cars with friends and acquaintances. Carpooling with total strangers also exists, surprisingly, at no more than the shared cost of gas. Most cities in America do not have a public transportation system as convenient as Japan’s. Even with options like carpooling and public transportation, many Americans prefer the individualism of driving in a car alone.

People read fewer and fewer books. But they might actually be reading more. Tech Life, a research group, recently conducted a survey of home leisure habits. Sixty percent of the respondents said they read the news online after 8:00 p.m. This time is usually the prime TV-watching hour. But more people seem to be spending this time on the internet. Additionally, mobile devices are becoming more common, especially in household these days. People can easily read on these thin and light devices wherever they are. TV-watching was once the enemy of reading. Now, it seems that reading is coming back, with the help of technology.

What is electricity? The idea of electricity is hard to understand because electricity has no shape. Electricity can be visible or invisible, depending on the situation. That is, you can see it sometimes, but cannot see it at other times.

Let’s take up an example of electricity that you can see. When you comb your hair, some of your hair may stand straight up. You may even hear a popping sound. You are seeing and hearing signs of electricity. Another example is lightning. Lightning sometimes comes with thunder, but more often it happens in the sky without making any noise.

Science explains that electricity is a flow of energy and it’s part of nature. This understanding of electricity started with a clever experiment. In 1752, Benjamin Franklin used a kite for an experiment one stormy night in Philadelphia. This is called Franklin’s kite-in-the-thunderstorm experiment. Through this experiment, Franklin discovered that lightning is a type of electricity.

Sound comes through your ears. It may be a human voice, the singing of birds, or music. But what is sound? What happens in your ear when you hear something?

First, let’s think about what sound is. A sound is a vibration and moves in waves. We call such waves “sound waves.” Sound waves are made when something vibrates. Sound waves can move through air, water, and solid materials. Sound waves travel at 343 m/s (meters per second) through the air, but they go faster through water and solid materials. You may wonder why. If you imagine dominos falling one after another, you’ll see why.

Now, let’s look into how we hear. When you hear something, sound waves enter your ear and go through a small tunnel in the ear. These sound waves pass through the tunnel to the small bones in the middle ear. These small bones vibrate. Then, in your inner ear, nerves catch the sound waves and send messages to your brain. Finally, your brain tells you what kind of sound you are hearing.

The first computer weighed almost 24,500 kilograms. Nowadays, a computer that is more powerful than the first computer weighs just a few grams. Once a computer became so light, it was easy to carry in your pocket. Now you may realize that the computer we’re discussing is your smartphone.

Yes, smartphones are new types of computers. They are light and portable. And with a single smartphone, you can make phone calls, send text messages to your friends, search for information on the Internet, and use social networking apps, and more.

You may wonder why we call this new type of phone “smart.” We call a smartphone smart because it is “really clever” and “super-efficient.” You may find the same usage of the word in new words such as “smart TV,” “smart home,” or “smart electric appliances.”