Our top picks for the best healthy gifts for kids will cover the active child, the snacker, the imaginative player, the STEM enthusiast, and more.

More than 2,300,000 limestone and granite blocks were pushed, pulled, and dragged into place on the Great Pyramid. The average weight of a block is about 2.3 metric tons (2.5 tons). How much is that?

Abstract: With the advancement of infrared technology, infrared small target detection plays a crucial role in precise guidance and warning systems, attracting widespread attention from researchers.