bạn tham khảo nhé,nếu ko thích thì cũng đừng cáo tội mình nha

A digital camera is a camera that stores pictures in electronic memory instead of film. Because of this, a digital camera can hold many more pictures than a traditional film camera. A digital camera can sometimes hold hundreds or thousands of pictures. Many use a memory card to store them. Most digital cameras can use a USB cable that connects into a computer to send pictures that are in the camera to the computer.

Digital photography is a kind of photography where a digital camera is used to take photos. Digital cameras use an image sensor instead of photographic film. Very often, they also use a memory card to store the photos in a digital format. Most photography is digital, though some photographers still use the old film cameras.

The majority of cameras are part of a mobile phone, called a "camera phone". They can send their pictures to other phones and other devices. Most camera phones do not make as good pictures as larger separate cameras do, especially where light is not bright.

Most digital cameras can serve as Video cameras. Some have a direct link to another computer where the data may be stored.

Light bulbs. Tham khảo nhé ~~

Lighting accounts for a fifth of our electricity bill. However, if we changed five of our conventional bulbs for energy-saving bulbs, we could save up to €60 on our annual electricity bill. We would also reduce greenhouse gas emissions by 340 kg. These figures may not seem significant individually, but if 20% of the Spanish population changed these bulbs, the total savings would be 480 million euros in electricity and three million tonnes less CO₂ emissions.

Despite this, energy-saving bulbs, technically called compact fluorescent lamps (CFL) are not very popular: Only 15% of the population uses them. This is mainly due to the price. Whilst a traditional 100W bulb costs €0.6, a 20W energy efficient one costs 14 times more: 9€. At first this difference may seem extreme. However, it is not if you take into account that between 75% and 80% less energy is used with these bulbs.

Other advantages are that they last eight times longer than conventional bulbs and provide the same light. In total, their useful life is between 8,000 and 10,000 hours. Also, incandescent bulbs are much less efficient because they only use 5% of the electrical energy they consume. The other 95% is transformed into heat and not used for lighting, thus producing unnecessary energy consumption.

Energy-efficient bulbs have been around for 25 years and they are now fully established. However, nowhere near as many of them are sold as traditional bulbs: 15 million units per year compared with 95 million. To encourage people to use these bulbs, the Government implemented the Energy Efficiency and Saving Plan, which included measures such as giving every Spanish household an energy efficient bulb throughout 2009 and another for 2010.