Concepts such as disease and health can be difficult to define precisely. Part of the reason for this is that they embody value judgments and are rooted in metaphor. The precise meaning of terms like ...

401(k) is a type of defined contribution plan with varying contribution limits based on age. Employers may match 401(k) contributions; withdrawals before age 59 1/2 can incur penalties. Other defined ...

The flu is caused by influenza viruses, not bacteria. Influenza can cause symptoms like fever, chills, and body aches. Influenza (referred to as the "flu") is a contagious respiratory disease caused ...

The winter solstice marks the shortest day of the year, bringing the least amount of daylight and the longest night. This year, the winter solstice will occur on Sunday, Dec. 21, at 10:03 am. EST when ...