Decoding the letter M

The letter M, lowercase m (pronounced /em/) normally represents IPA phoneme /m/. For examples see IPA phoneme /m/.

Exception
 * Silent m: mnemonic

Assimilation
Before /f/ or /v/, /m/ and /n/ may be neutralized and pronounced [ɱ], a labiodental nasal. For this reason someone may hear "pamphlet" [ˈpæmflət] as and be surprised by the "m" in the spelling. However, the opposite is much more common, hearing /nf/ as /mf/.

Before /p/ or /b/, /m/ and /n/ may be neutralized and pronounced [m] as in an alternative pronunciation of input as. There are no minimal pairs in which the difference is /np/ and /mp/, or /nb/ and /mb/. This type of assimilation explains that someone who hears "impossible" [ɪmˈpɒsəbl] as may be surprised that the spelling has an "m".