In Japanese, this kana is used almost exclusively as a particle; as such, the katakana form (ヲ) is fairly uncommon in everyday language — mostly used as a stand-in for its hiragana counterpart in texts that need to be written entirely in katakana.
Generally, it represents Template:IPA-ja, although some dialects retain the pronunciation [wo],Template:Citation needed which is also often used in songs. It is also occasionally pronounced this way when stressing the particle, especially to clarify when someone misunderstands what has been said.
A "wo" sound is usually represented in katakana as ウォ instead. For example, ウォークマン (Wōkuman, "Walkman") and ウォッカ (Wokka, "Vodka")