Differentiating consonants with same location and manner of articulation
In the articulation of bilabial plosives, 4 phones are defined by the characteristics voiced/unvoiced and aspirated/unaspirated: [p], [pʰ], [b] and [bʱ]. In different languages only some of these may occur and the number of phonemes formed may be different again.
Pattern
Language(s)
Explanation
English
Phones [p] as in "spin" and [pʰ] as in "pin" both occur, but are allophones of the phoneme /p/ and no minimal pair can be found to distinguish them, but the word "bin" shows that the phone [b] forms a phoneme /b/ separate from /p/.
Mandarin
Only phones (and phonemes) [p] and [pʰ] occur. In the Pinyin transcription /pʰ/ is written "p" and /p/ is written "b" (using the two available Latin letters for the two phonemes).
French/Portuguese
In romance languages and other European languages only phones (and phonemes) [p] and [b] occur.