《戴孝》

您可曾注意在丧礼常见到丧家衣服上戴着的小四方型布?
您知道那是什么吗?
佛教和道教的殡葬礼使用布制成的徽章 – 统称「戴孝」,以表示往生者与其家属之间的关系。不同的籍贯都有一套略有不同的孝制设计。在旧时代,戴孝也被用作哀悼的标志,丧亲家属会戴孝49天。现在,丧亲家属多半在葬礼后就取下孝制(也就是脱孝)

What is the fabric square badge seen on clothing used for during funeral?
In the past, these badges are used by Taoists as a tool to signify the relationship between the living family members and the deceased. Different dialect groups have slightly different set of badge design/ combination. Buddhist also uses badges now.
In olden days, it is also used as a sign of mourning where bereaved family members wear them every day for 49 days. However, in current times, this tradition has been simplified to the badges being worn till the end of funeral day only.