Robotics

Robots have been around since the twentieth century in one form or another, but it won’t be until the twenty-first century that they will become truly common and useful. Performing everything from fire-fighting to carpentry, by the end of the century every house will have at least one robot programmed to perform any number of tedious or dangerous chores humans would rather not deal with, and they will be perfect to leave at home to walk the dog (heck, your dog might even be a robot) and keep an eye on the house when you’re away. Their military applications are even more promising, with robots being used to clear mine fields and otherwise perform missions deemed too dangerous for their human counterparts. How smart will they be? Only as smart as you want them to be; they’ll still be dependent upon human beings for their programming and maintenance after all, so don’t look for them taking over the world just yet.

Source: http://www.toptenz.net/top-10-inventions-of-the-21st-century.php