A random park. Someone has strung a set of colourful flags beneath the largest tree.

Holding the centre of the flag is a drawing of the windhorse, a legendary creature that carries the prayers and mantras of the flag out into the world with the speed and power of the wind.

Traditionally, prayer flags are used to promote peace, compassion, strength, and wisdom. The flags do not carry prayers to gods, which is a common misconception; rather, the Tibetans believe the prayers and mantras will be blown by the wind to spread the good will and compassion into all pervading space. Therefore, prayer flags are thought to bring benefit to all.

By hanging flags in high places the Lung ta will carry the blessings depicted on the flags to all beings. As wind passes over the surface of the flags, which are sensitive to the slightest movement of the wind, the air is purified and sanctified by the mantras.

The prayers of a flag become a permanent part of the universe as the images fade from exposure to the elements. Just as life moves on and is replaced by new life, Tibetans renew their hopes for the world by continually mounting new flags alongside the old. This act symbolizes a welcoming of life’s changes and an acknowledgment that all beings are part of a greater ongoing cycle.

— Wikipedia.