camelCase and snake_case are two naming conventions for multi-word identifiers in code. camelCase joins words and capitalizes each after the first, like emailAddress. snake_case separates words with underscores in lowercase, like email_address. Both are widely used, but different ecosystems favor different styles.
Consistency matters more than the choice itself, but conventions run deep: JavaScript and Java lean camelCase, while Python and Ruby lean snake_case. Mixing styles in one codebase looks sloppy and causes friction, so teams standardize per language.
