Silver is a precious soft metal with some interesting properties; It's the most electrical conductive, thermal conductive and reflective metal available making it a very useful material for the Industry. You can find Silver used in solar panels, batteries, electronics, mirrors, medicine and of course in silverware, jewelry and investment coins.
Silver as an investment
Silver is not as expensive as Gold but this hasn't always been the case. Like gold it can be used as a hedge against economic problems like inflation. You can buy silver as an investment either on paper speculating on it's price or physical where you can buy a actual piece of silver, often in coin or bar form.
Taxes on silver vary from country to country. Where gold is often tax free silver is likely to be subject to VAT. In Europe it's often the case that you pay your high VAT rate over silver bars where with silver coins you only pay taxes over the profit margin of the retailer (the so called premium). This often makes it more interesting to buy silver in coin form over bars.