difference between Nihonbashi and Nihombashi

I am going to visit Japan and going to stay in Tokyo for some work at Takashimaya Nihonbashi.I want to know the difference between Nihonbashi and Nihombashi. At some places it is written Nihonbashi and at some places it is written Nihombashi.

There is none. Nihonbashi and Nihombashi are two ways to transcribe 日本橋 into Latin characters. Remember that any time you see a Japanese word written in Latin characters, it is not the "real" word, just a transliteration.

Although, there is no difference, I think it's more common for it to be romanised as Nihombashi. The reason for why there are 2 different romanisations is because it uses the hiragana ん. This would normally be pronounced as an n, but sounds more like an m when it comes before a syllable starting with b or p. For words that follow this rule, people generally write the ん character as m, but there is no one correct way to write it, as there are different romaji systems, and romaji isn't native to Japanese. This is also used for other words such as Tempura and Shimbashi.

Same.
Not typo.
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