National Griper's Day is celebrated on April 15th and provides an opportunity for individuals to voice their complaints in a lighthearted manner. The day encourages people to share their pet peeves with friends, family, or coworkers, fostering a sense of community through shared frustrations. Participants are invited to vent about everyday annoyances, such as traffic or technology issues, while maintaining a playful atmosphere. Customs include hosting "vent and listen" gatherings, where individuals take turns expressing their grievances, and writing complaints on sticky notes to display common irritations. The focus is on constructive and harmless complaints, promoting connection and empathy among participants. Overall, the day emphasizes the therapeutic value of sharing grievances, often leading to laughter and relief.