[from SF fandom via Usenet; abbreviation for ‘In My Humble
Opinion’] IMHO, mixed-case C names should be avoided, as
mistyping something in the wrong case can cause hard-to-detect errors
— and they look too Pascalish anyhow.
Also seen in variant
forms such as IMNSHO (In My Not-So-Humble Opinion) and IMAO (In My Arrogant
Opinion).