A week is a fundamental unit of time commonly used globally, particularly in civil calendars, and is defined as a period of seven consecutive days. This unit measures the passage of time and is widely used to organize schedules, plan activities, and track durations over short to medium-term periods. The symbol for a week is often abbreviated as "wk" or "week," and it is a standard unit in many cultures and industries. A week typically begins on a specific day, usually Monday in business and professional settings or Sunday in personal and religious contexts. The week is essential in both practical and scientific contexts, as it provides a manageable and relatable timeframe for planning, data collection, and analysis. Its widespread use facilitates international communication and coordination, and it plays a critical role in structuring workweeks, academic calendars, and social routines.