Tagging is the act of writing your name or your own sign on walls, trains, bridges and other public places without being allowed to. The name you write is a tag: short, quick, always the same, so people recognise it. Tagging is done fast — often in seconds, often at night — because the person doing it does not want to be caught.

Tagging簽名式塗鴉 is the act of writing your name or your own sign指的是在牆上、火車、橋樑等公共場所 on walls, trains, bridges and other public places without being allowed to未經允許寫上自己的名字或個人標記的行為。The name you write is a tag你寫上的那個名字叫做 tag（塗鴉簽名）: short, quick, always the same簡短、快速、永遠一樣, so people recognise it讓人一看就認得。Tagging is done fast這種塗鴉做起來很快 — often in seconds, often at night常常只花幾秒鐘，常常在晚上進行 — because the person doing it does not want to be caught因為做這件事的人不想被抓到。

Notice the difference between tagging and the wider word graffiti. Graffiti is the whole family, from one rude word scratched on a desk to a whole wall painted like a picture. Tagging is one narrow member of that family: writing a signature, over and over. Painting a large, careful, coloured picture on a wall is usually called doing a piece or painting a mural instead.

Notice the difference請注意兩者的差別 between tagging and the wider word graffiti在這種簽名式塗鴉和更廣義的 graffiti（塗鴉）之間。Graffiti is the whole family graffiti 是整個大家族, from one rude word scratched on a desk to a whole wall painted like a picture從桌上刻的一個粗話，到整面牆畫得像一幅畫都算。Tagging is one narrow member of that family而簽名式塗鴉是這個家族裡狹窄的一支: writing a signature, over and over就是不斷地寫同一個簽名。Painting a large, careful, coloured picture on a wall畫一幅大幅、精細、有顏色的牆畫 is usually called doing a piece or painting a mural instead通常會另外叫做「畫一幅作品」或「畫壁畫」。

Because tagging is against the law, the word usually appears in unhappy sentences — city councils complaining about it, shop owners cleaning it off, police reports. It is a normal noun and you can use it comfortably in writing.

Because tagging is against the law因為這種塗鴉是違法的, the word usually appears in unhappy sentences這個詞通常出現在不太愉快的句子裡 — city councils complaining about it像市議會抱怨這件事, shop owners cleaning it off店家把它清掉, police reports或警方報告。It is a normal noun它是一個普通名詞, and you can use it comfortably in writing你可以放心地在寫作裡使用它。

Grammar note: tagging is the -ing form of the verb tag, so it works both as an action noun ("Tagging is a problem here") and inside a verb phrase ("He was tagging a wall").

Grammar note文法小提醒: tagging is the -ing form of the verb tag這個詞是動詞 tag 的 -ing 形式, so it works both as an action noun所以它既可以當動作名詞用 ("Tagging is a problem here"像「Tagging is a problem here」) and inside a verb phrase也可以放進動詞片語裡 ("He was tagging a wall"像「He was tagging a wall」)。

And be ready for the completely separate everyday sense — tagging a friend in a photo online, tagging files, tagging clothes with prices. Same word, no crime involved.

And另外 be ready for the completely separate everyday sense也要留意一個完全不同的日常意思 — tagging a friend in a photo online像在網路照片上標記朋友, tagging files, tagging clothes with prices替檔案加標籤、替衣服貼價錢標籤。Same word, no crime involved同一個字，但沒有犯罪的意思。