Service classification rules: specific descriptions and essential character determine taxable category; exemptions do not alter classification. Section 65A requires matching each service to the relevant sub clause of clause (105); where multiple sub clauses apply, prefer the most specific description, and if parity persists use the first occurring sub clause. For composite services, classify by the service that imparts the essential character if specificity cannot resolve classification. Determine whether taxation depends on the nature of the service or the person providing it before applying these rules. Exemption notifications do not alter statutory classification and must be applied only after classification is settled.