Shoko refers to burning incense in Buddhism. It especially means to pray to Buddha or the deceased with burning incense. It is also called Funko. It is the antonym of Zuko.
There are two ways - burning senko (an incense stick) and burning makko (incense powder).
Senko shoko (burning an incense stick) is done for daily praying, and is generally called 'senko o ageru (offering an incense stick).'
Makko shoko (burning incense powder) is done by picking up crumbled incense (makko) and sprinkling it in the koro (incense burner) to burn. It is done on occasions such as a wake, funeral, and a memorial service. This is the one generally called Shoko. Therefore, makko is also called Shoko, and makko is rather known by this name.
It is to get rid of impurities of the body and soul, so it is supposed to be a manner when praying with a pure heart. Shoko is done with the right hand, while holding juzu (beadroll) in the left hand. The incense is picked up by the thumb, index finger and middle finger, but the manner depends on the religious school.
School specific differences
They have Shoko three times and also put up three senko. It is supposed to cleanse three kinds of Karma - actions, words and thoughts. There are other theories that it is to devote three treasures of Buddhism, 'Buddha, sutras and priesthood,' and that it is to cast away three poisonous earthly desires (greed, anger and complaint) one by one.
They have Shoko twice and put up one senko. First they burn a pinch of incense after lightly holding it above the head while bowing with the right hand, and then burn another without holding it above the head. The first incense to burn is called shuko (main incense), and the next one to burn is called juko (sub incense).
Shinshu sect Otani school
They have Shoko twice without holding the incense in front of the forehead. They break and lay a senko without standing it up.
Jodo Shinshu Hongan-ji school
They have Shoko once without holding the incense in front of the forehead. They break and lay a senko without standing it up.
Nichirenshu sect, Jodoshu sect, etc. They have Shoko three times and put up one senko.