Introduction

Buddhism is not concerned solely with the individual path to liberation. A lot of Buddhist rites are answers to the most common religious needs in every society, like funerals and festivals. Nonetheless, all these practices are consistent with the basic doctrine of Buddhism.

Main rites: funerals

In most Buddhist traditions, funeral rites are extremely important because they are considered to be the last chance to help the dead person to attain a more favorable rebirth in terms of enlightenment. It is believed that the detachment of the soul from the body is a gradual process and that it is possible to affect the Karman of the dead person's soul with the help of the living. For this reason it is often customary to recite Sutras and preach religious teachings in the presence of the deceased. This has multiple purposes and meanings: reading Sutras produce good Karman that can be devolved in favor of the deceased, while the Buddhist teaching about the impermanence of everything are meant to help the deceased soul to accept his fate, as well as to help the relatives to accept their beloved's departure. The ceremonies vary from country to country, but cremation is the most common practice. See source 1 

Main rites: spirits-related practices

It may come as a surprise to those who equate Buddhism solely with its intellectual and mystical traditions to learn that demons, ghost or ancestors' spirits have been a central aspect of its history, even in modern times. In its progress through Asia, Buddhism absorbed in its worldview (see section 3 and Skillful Means in section 6) pre-existent cults and practices in India as well as in all Asia, allowing them to flourish in tandem with Buddhism. All classes of beings, including beings of the lower realms such as demons, animals, and ghosts, may improve their spiritual status by attaining a higher birth in the human or divine realms. Therefore demons are not doomed to be demons forever. Exorcisms are meant to sooth these demons or ghosts, through offerings and recitation of Buddhist teaching. This in order to transform them in benevolent entities or, in case of ghost of human beings, to haste their next rebirth. Another important practice is worship  of ancestors, for whose sake Sutras are recited and food is offered. See source 2.

Main rites: Buddhist Feasts

There are many holy days held throughout the year by the Buddhist community. Some holy days are specific to a particular Buddhist tradition or ethnic group. The Buddhist New Year's festivals, for example,  depends  heavily on the country of origin or ethnic background of the people. They demonstrate Buddhism’s ability to co-opt preexisting local traditions. On the occasion of the New Year, images of the Buddha in some countries are taken in procession through the streets. Worshipers visit Buddhist sanctuaries and circumambulate a Stupa (see section 9) or a sacred image, monks are given food and other gifts. Typically on a festival day, lay people will go yo the the local temple or monastery and offer food to the monks, take the Five Precepts (see section 8) and listen to Buddhist teachings,  In the afternoon, they distribute food to the poor to make good Karman. The most significant celebration common to virtually all Buddhist is the Vesak (see below).

Sources' analysis and comment

Source 1

The three major events of the Buddha’s life —his birth, enlightenment, and entrance into Parnirvana— are commemorated in all Buddhist countries but not everywhere on the same day. In Theravada countries the three events are all observed together on Vesak, the full moon day of the sixth lunar month, which usually occurs in May. In Japan and other Mahayana countries, however, the three anniversaries of the Buddha are observed on separate days.

On Vesak day, devout Buddhists  are expected  to assemble in their various temples before dawn for the ceremonial, singing hymns in praise of the Three Jewels, i.e. the Buddha, the Darma andthe Sangha (see section 9).  Devotees may bring simple offerings of flowers, candles and joss-sticks. These symbolic offerings are to remind followers that just as the flowers would shortly wither away and the candles and joss-sticks would soon burn out, so too is life subject to decay and destruction. Devotees are enjoined to make a special effort to refrain from killing of any kind. They are encouraged to partake of vegetarian food for the day.

In Indonesia, thousands of Buddhist monks join together to repeat chants and meditate as they circle the famous Borobodur temple (see also Buddhism Module 2, section 3) in praise of the Three Jewels. Monks celebrate the special day by transporting flames (which symbolize enlightenment) that ultimately are sent by lay people to the sky by means of floating lantern.

Link to other modules:
HInduism sec. 12
Judaism II Themes sec. 4
Buddhism II. Diffusion in the World sec. 2