What is a computer virus?

A virus is a malicious software program that infects computer files or hard disk drives and then makes copies of itself. Many activities that kids do online can leave computers vulnerable to viruses. E-mail attachments are a common means of distributing viruses, but viruses can also be downloaded when you share files and open instant message attachments. In order to keep your computer safe, never open an e-mail attachment you haven’t requested.

Send an e-mail to friends to confirm that they meant to send you an attachment. Also, you can configure your instant messaging program so you can’t receive files from other users. Never download any program without checking with a parent first. You can protect your computer by always running up-to-date firewall software, by running antivirus software regularly, and by periodically scanning your computer for spyware or other unwanted software and immediately removing it.

Why should I visit the library often?

Libraries offer books for people of all ages, and much, much more—they are places of learning and discovery for everyone. Besides books, public libraries offer videos, DVDs, free access to computers and the Internet, and many literacy-related programs.

For elementary school children, there are variations of the read-alouds and storytelling hours that often include discussions and presentations by the children themselves, as well as summer reading programs. For middle-school kids, there may also be book talks, summer reading programs, creative writing seminars, drama groups, and poetry readings. The more you read, the more you learn! In addition, the library is a place to find information and help with schoolwork. Your school library may offer some of these services as well.

What does my brain do, besides think?

The brain is the body’s command center; everything we do—eating, talking, walking, thinking, remembering, sleeping—is controlled and processed by the brain. As the most complex organ in the human body, the brain tells us what’s going on outside our bodies (whether we are cold or hot, for instance, or whether the person we see coming toward us is a friend or a stranger) as well as what’s going on inside our bodies (whether we have an infection or a broken bone, or whether we feel happy or sad).

The key to the body’s nervous system, the brain contains between 10 billion and 100 billion nerve cells, or neurons. Neurons combine to form the body’s nerves, thin cords that spread from head to toe and all parts in between. Neurons take in and send out electrical signals, called impulses, that control or respond to everything your body does and feels. The brain is like a very busy, high-speed post office, constantly receiving messages and sending them out all the time; it handles millions of nerve impulses every second.

Which religions are the most widely practiced around the world?

Today there are some 4,300 religions in the world. Nearly 75 percent of the world’s population practices one of the five most influential religions of the world: Christianity, Buddhism, Hinduism, Islam, and Judaism. Christianity, which is based on the teachings of Jesus Christ, who preached in Palestine about 2,000 years ago, is the most widely practiced religion in the world today, with 2.1 billion followers.

The second most practiced religion is Islam, with 1.3 billion followers.

Where can you stand in four states at the same time?

The Four Corners, located 40 miles (64 kilometers) southwest of Cortez, Colorado, is the only place in the United States where four states come together at one place. Arizona, New Mexico, Utah, and Colorado meet at the Four Corners. Here, a person can put each of his or her hands and feet in four states at the same time. The unique landmark is on Navajo Nation land and is open for visits from the public. The area surrounding the monument is also Indian land, which includes part of New Mexico, Utah, and Arizona and covers 25,000 square miles (64,750 square kilometers). The Four Corners Monument was originally established by the U.S. Government Surveyors and Astronomers in 1868 with the survey of Colorado’s southern boundary. Surveys followed of New Mexico’s west boundary and Utah’s east boundary in 1878.

The northern boundary of Arizona was surveyed in 1901. A small permanent marker was made in 1912 to show where the boundaries of the four states intersect. The Monument was refurbished in 1992 with a bronze disk embedded in granite. The disk shows the state boundaries and each state’s seal rests within that state’s boundary.

Why do we say “Goodnight, sleep tight”?

Sometime during the sixteenth century, British farmers moved from sleeping on the ground to sleeping in beds. These beds were little more than straw-filled mattress tied to wooden frames with ropes.

To secure the mattress before sleeping, you pulled on the ropes to tighten them, and that’s when they began saying, “Goodnight, sleep tight.”

Which planet could melt metal?

Most people think that Mercury is the hottest planet because it is nearest to the Sun. However, Venus, the second nearest planet, is the hottest because it has an atmosphere. Its atmosphere is primarily composed of carbon dioxide, which acts like a greenhouse.

The solar heat enters Venus’s atmosphere, but it cannot leave, heating the planet’s surface to about 900 degrees Fahrenheit (482 degrees Celsius). This temperature is hot enough to melt several metals, including lead, tin, and zinc.

Why is natural ability called “talent”?

In the ancient world a talent was a unit of weight used to value gold and silver. Today’s use of the word comes from the Book of Matthew, Wherein three servants are given equal amounts of money, or talent, by their master. Two invest wisely and profit while the third buries his and doesn’t.

That parable is how talent came to refer to the natural gifts we are all born with. The moral of the tale is that we must use our talents wisely or we will fail.

How can cows make so much milk?

A cow, like all mammals, produces milk to feed its young. If its calf nurses regularly, the mother cow’s mammary glands will produce enough milk to give the baby animal all the food it needs. Gradually a calf will nurse less as grass and other feed makes up more of its diet. A mother cow, in turn, will produce less milk until it is no longer needed. But by milking the cows regularly—two or three times a day—dairy farmers can cause the cows to continue producing milk. Certain breeds of cows are particularly good at milk-making, producing 18–27 pints (around 2–3 gallons, or 10–15 liters) each day.

A cow’s large, round udder, located on its underside, has four nipples, or teats, that are squeezed to release stored milk. While once done by hand, milking is done on modern dairy farms by machines with suction hoses, which do the job more quickly and cheaply. Tank trucks collect milk from farms daily and take it to processing plants where it is pasteurized (made germ-free) and used to make dairy products like cheese, butter, and ice cream.

Why is a misleading sales pitch called a “song and dance”?

During the days of travelling vaudeville shows, there were featured stars, and there were fillers. The fillers were the comics who were hired to keep the audience amused by telling jokes within a song and dance routine until the next headliner was ready to come on stage. Since then, any well-rehearsed routine that is intended to divert your attention from what you came to see has been called a “song and dance.”