In Japan, it's a custom to give gifts periodically to people such as co-workers, bosses, relatives, teachers, friends, and so on.
The giving of end of year gifts is called oseibo, and people send these gifts during December.
(It's best to send the gifts by the 20th if you are in Japan).
Despite it's timing, oseibo isn't related to Christmas.
The cost of a gift ranges from 3000yen to 10000yen, and the average is about 5000yen.
Popular items for oseibo are ham, cooking oil, gift certificates, beer, canned food, coffee, seasonings, seaweed, seafood, fruits, and more.
The type and cost of gift depends on your relationship with the recipient.
Usually people give the most expensive gifts to their bosses at work.
Department stores display many types and sets of oseibo gifts during December and are crowded with many customers.