The purpose of Child Health Day is to help raise an awareness and a commitment to teaching children and parents the benefits of good health. This event is annually celebrated on the first Monday of October. The day was proclaimed in 1928 by Calvin Coolidge to increase awareness of health issues facing the children in the U.S. including health issues, healthy eating, fitness, child's development, immunizations, preventing injuries, and more.

Columbus Day commemorates Columbus' famed expedition across the Atlantic Ocean, in which he hoped to find a naval route to India. Instead, he found an entire continent that was mostly unknown to Europeans at the time. While other Europeans had sporadically visited the Americas earlier, and there are varied theories of even earlier contact by East Asians, Phoenicians, and others, Columbus' expedition triggered the great wave of European interest in the New World. Unlike the earlier visitors, Columbus aggressively popularized his discoveries and arranged for return voyages. Columbus day is celebrated in America on the second Monday in October.

Global Handwashing Day is a campaign to motivate and mobilize millions around the world to wash their hands with soap. The campaign is dedicated to raising awareness of handwashing with soap as a key approach to disease prevention. It was invented at the annual World Water Week 2008, which was held in Stockholm from August 17 to 23 and initiated the Public Private Partnership for Handwashing (PPPHW). Global Handwashing Day took place for the first time on October 15, 2008, the date appointed by UN General Assembly in accordance with year 2008 as the International Year of Sanitation. The theme for Global Handwashing Day's inaugural year was Focus on School Children. The members pledged to get the maximum number of school children handwashing with soap in more than 70 countries. The tradition goes on today to help children around the world prevent infection and the spread of disease by learning to wash their hands.

National Boss Day is celebrated on October 16 in the United States. The day is meant to celebrate bosses who have been fair and kind throughout the year. The origin of Boss's Day can be traced back to 1958 when Patricia Bays Haroski registered "National Boss' Day" with the U.S. Chamber of Commerce in 1958. Patricia was working as a secretary for State Farm Insurance Company in Deerfield, Illinois. While working, she became aware of the challenges her boss (who also happened to be her father) had to face. In order to show her admiration and respect for her boss, she invented Boss Day. She chose her dad's birthday on the 16th of October as the date. If it falls on a weekend, it is celebrated on the work day closest to the 16th.

Sweetest Day is a day similar to Valentine's when people share romance or appreciation for one another. It occurs in October on the third Saturday of the month. The holiday is said to have begun in the city of Cleveland, Ohio in 1922. Candy store employee Herbert Birch Kingston put together a group of citizens to provide small gifts to homeless people, orphans, and others who had fallen on hard times. This tradition now seems to largely involve giving small presents, such as cards, candy and flowers, to family, friends, and sweethearts.

The first moon after the Harvest Moon is the Hunters Moon, so named as the preferred month to hunt summer-fattened deer and fox unable to hide in now bare fields. Like the Harvest Moon, the Hunters Moon is also particularly bright and long in the sky, giving hunters the opportunity to stalk prey at night. Probably because of the threat of winter looming close, the Hunters Moon is generally accorded with special honor, historically serving as an important feast day in both Western Europe and among many Native American tribes. Note that some years the Harvest Moon falls in October instead of September. The Hunters Moon of October is sometimes referred to as the Blood Moon or Sanguine Moon, as the Native Americans named this bright moon for obvious reasons. Other names for this full moon include the Travel Moon and the Dying Grass Moon. A full moon is a lunar phase that occurs when the geocentric apparent longitudes of the sun and moon differ by 180 degrees; the moon is then in opposition with the sun. At this time, as seen by viewers on earth, the hemisphere of the moon that is facing the earth (the near side) is fully illuminated by the sun and appears round. Only during a full moon is the opposite hemisphere of the moon, which is not visible from earth (the far side), completely unilluminated. As a lunar month is about 29.531, the period between full moons can be either 29 or 30 days.

Halloween is a holiday celebrated on the night of October 31. Halloween activities include trick-or-treating, ghost tours, bonfires, costume parties, visiting "haunted houses" and carving jack-o-lanterns. Irish immigrants carried versions of the tradition to North America in the nineteenth century. Other western countries embraced the holiday in the late twentieth century. Halloween is celebrated in several parts of the Western world, most commonly in Ireland, the United States, Canada, Puerto Rico and the United Kingdom and occasionally in parts of Australia and New Zealand.