The word "代码" (dàimǎ) is formed by combining two individual characters, each contributing a core concept to create a new, unified meaning. The first character, "代" (dài), carries the fundamental idea of "substituting for" or "acting on behalf of". The second character, "码" (mǎ), essentially means "number", "tag", or "symbol". When fused, the compound conceptually represents "symbols that stand in for or represent something else", directly and efficiently capturing the essence of "code" as in programming or ciphers, where symbolic representations substitute for instructions or information.