10th-century inventions

writing implement

10th Century firearm of Chinese origin

thumb|upright|right|Italian hauberk from the late 15th century A hauberk or byrnie is a mail shirt. The term is usually used to describe a shirt reaching at least to mid-thigh and including sleeves. A haubergeon ("little hauberk") refers to a smaller mail shirt, that was sometimes sleeveless, but the terms are occasionally used interchangeably. Mail armor, likely invented by the Celts, became widely adopted for its flexibility and spread throughout Europe and Asia, becoming a staple in Roman legions and medieval warfare. By the 11th century, the hauberk evolved into a knee-length, sleeved mail