They come in a variety of colors, shapes and sizes. The familiar blue, green, yellow and red blocks can be used to build miniature castles, spaceships and cars.
But, as one Missouri woman proves, Legos can also be used to build prosthetic limbs.
Christina Stephens, 31, of St. Louis, lost part of her leg earlier this year after her foot was crushed while changing the brakes on her car.
When a coworker jokingly suggested she build a prosthetic leg out of Legos, she laughed all the way to YouTube.
Below is the video Stephens posted last month, which has gained more than 1 million views.