Science and technology can bring benefits to people's lives. A benefit is a positive effect of a product or a process.
In the early 20th century there were scientific developments in the use of radioactive materials. Without these developments, the medical world wouldn't have benefitted from advances such as the gamma camera.
The use of nuclear fission for the production of electricity in power stations has led to a reduction of the emission of greenhouse gases.
Fuels cells power electric cars and reduce emissions of air pollutants where the car is being driven.
Equally, new advances can also give rise to risks. A risk is an estimate of the likelihood that an undesired outcome will happen. The size of a risk is estimated based on the chance of it happening in a large sample over a specified length of time.
Advances in science and technology can bring risks. Scientists devise ways to reduce these risks.
At the beginning of the 20th century no one knew the dangers of radioactive materials and this led to the death of many workers.
There have been a number of nuclear disasters, such as Chernobyl and Fukushima, and these have led to many deaths.