Buddha Dharma Sangha in Chinese / Japanese...

佛法僧 is the Buddha, Dharma, and Saṅgha.

These three characters are the “Triple Gem” of Buddhism or the Buddhist Trinity.

三寶 is the title for “Three Precious Treasures of Buddhism” or “The Triple Gem.”

These three treasures are the Buddha 佛, the Dharma 法 (teachings or the law of the Buddha), and the Sangha 僧 (the community of monks or followers).

This term is used by most (perhaps not all) Buddhists in China, Japan, and South Korea (written the same in the original form but pronounced differently in each language). Non-Buddhists may just read this as “Three Treasures” without the religious context. For instance, there is also a “Three Treasures of Chinese Medicine” that is sometimes titled the same way.

In modern Japanese and Simplified Chinese, this is written 三宝 instead of 三寶.

南無三寶 means to take refuge in the three treasures (of Buddhism).

This starts with the phonetic “南無” or “Namo/Namu” trying to sound like the original Pali or Sanskrit, followed by “三寶” being more literally the three treasures.

歸依三寶 means to take refuge in the three treasures (of Buddhism).

This is the literal (there is also a partially-phonetic version) way to express taking refuge in the three treasures by the actual meaning of the characters.