In one sentence, describe what the following article is about:

Winter is a great time to get outdoors and have fun. Whether you're interested in physical activities like skiing or simply playing in the snow in your yard, it's important to dress warm - but not so warm that you can't stop sweating - and protect your body against heat loss. You lose the most heat from your head, hands, and feet, so make sure you cover these extremities as well as your core (chest and abdomen). If you or others experience any of the following symptoms of hypothermia, get indoors immediately and call emergency services to find out how to proceed:  involuntary shivering inability to perform motor functions confusion loss of coordination slurred speech irrational behavior Depending on your age, it may have been many years since you've played in the snow when you were a child. But spending time building things in the snow or having outdoor adventures with friends/family can be fun at any age. Just make sure you dress appropriately, and make a mug of steamy hot chocolate to warm up when you return indoors.  Have a snowball fight with friends. Build a snowman. Make snow angels. Build a snow fort. Ice skating is another great way to spend time with your family and reconnect with a fun childhood activity. You can skate at indoor rinks or outdoor rinks, if they're available in your community, and admission is usually very cheap (and sometimes free).  Find ice rinks near you by searching online. If you have your own skates that still fit, bring them. If not, call ahead to make sure the rink has rental skates available. . If you grew up in an area with snowy winters, you probably went sledding at some point as a kid. Sledding is still a fun activity, even for adolescents and adults. You can sled at your old neighborhood hill, or check online to see if any ski hills offer snow tubing. Tubing is like sledding, only you're towed up a hill and get to ride to the bottom on an inflatable tube, often over jumps and ridges. If you live near a park or rural area, you may want to try your hand at cross-country skiing or snowshoeing. These activities are not as fast-paced as downhill sports, but they offer solitude (or companionship) through a quiet, peaceful winter wonderland.  Call your local sporting goods stores to see if you can rent cross-country skis or snowshoes. If you don't have any luck at a sporting goods store, you might try a nearby ski resort. Many ski resorts offer cross-country ski rentals in addition to their downhill equipment, and some may even have well-groomed cross-country trails at the resort. . Downhill skiing and snowboarding are tremendously fun sports, but they can also be incredibly dangerous if you don't know what you're doing. It's important that you take lessons and start out slowly so you don't injure yourself or put others at risk.  Start out slow. If you've never skied before, stick to the "bunny hills" that are meant for beginners. Most ski hills are rated with a colored shape to indicate difficulty. Those ratings are consistent throughout each resort, meaning that each hill of the same rating will be about the same level of difficulty.  Remember that ratings are only consistent within that resort. An easy hill at a resort in Colorado would probably be ranked as an intermediate or difficult hill in Vermont, for example. A green circle means the hill is easy, and generally suitable for beginners (though you should check with a ski attendant if it's your first time). A blue square means the hill is slightly more difficult, and may be best for skiers with intermediate experience. A black diamond means that a hill is one of the most difficult ski trails. Black diamond trails should only be attempted by highly-skilled skiers with many years of experience. Double-black diamond means that the hill is the most difficult and requires extra caution than even a regular black diamond hill. Never attempt a black diamond or double-black diamond if you aren't a very talented, highly-experienced skier. Orange oval means that the hill is a freestyle terrain. These hills typically require a lot of experience and proficiency, and should only be attempted by professionals. If you live in a warm weather climate, you may be able to play outdoors year-round. Even if you live in a colder climate, however, many cities plan fun outdoor activities in the winter - just be sure to dress warm enough for whatever activities you have planned. Check online to see what outdoor events your town or city hosts each winter. Local events at your park may include:  hot chocolate ice skating holiday light shows tree decorating ceremonies If you live in a warmer climate, you may be able to go running outdoors during winter break. Make sure you pace yourself if you're new to running, and don't try to push yourself too hard or too fast.  Find jogging trails near your home, or simply go for runs around your neighborhood (if it's safe to do so). Dress appropriately. If you get too bundled up, you'll sweat profusely and end up cold; if you dress too lightly, you may be freezing, and could get sick as a result. If you live in a warm climate and are able to ride your bike safely in your area, you may want to explore your community by bike. Bicycling is a great way to get fresh air and exercise while exploring new, off-the-path places right in your neighborhood. However, biking can also be dangerous, especially if you live in a high-traffic area. For this reason, it's important to take every precaution to ensure your safety.  Always wear a properly-fitted bicycle helmet, no matter how old you are or how far you'll be riding. Check your tires and brakes before riding. Make sure your tires are properly inflated, and tap your brakes in the driveway before leaving your home to ensure that they'll work when you need them. Children under 10 years of age are typically supposed to ride on the sidewalk, while adolescents and adults are usually expected to ride in the street. However, if you feel unsafe riding in the street, it's best to choose the sidewalk to prevent an accident. Check the laws in your town or county online, as some municipalities prohibit riding bicycles on the sidewalk. Breaking these laws may result in a fine if a police officer stops you. Wear bright colors so that other motorists can see you, and try to avoid riding at night. If you must ride at night, take extra precautions and wear reflectors and bicycle lights. Keep at least one hand on the handlebars at all times, but try to keep both hands engaged by carrying groceries or other items in a backpack. Ride in the same direction as traffic is moving, and follow all traffic signs/signals. Be alert and use signals to indicate to others when you'll be turning or braking.

Summary:
Dress warm and know the signs of hypothermia. Play in the snow. Visit your local ice rink. Go sledding or snow tubing Enjoy cross-country skiing or snowshoeing. Try downhill skiing or snowboarding Visit your local park. Go running. Bike around your neighborhood.