History
The concept of record can be traced to various types of tables and ledgers used in accounting since remote times. The modern notion of records in computer science, with fields of well-defined type and size, was already implicit in 19th century mechanical calculators, such as Babbage's Analytical Engine.
Records were well established in the first half of the 20th century, when most data processing was done using punched cards. Typically each records of a data file would be recorded in one punched card, with specific columns assigned to specific fields.
Most machine language implementations and early assembly languages did not have special syntax for records, but the concept was available (and extensively used) through the use of index registers, indirect addressing, and self-modifying code. Some early computers, such as the IBM 1620, had hardware support for delimiting records and fields, and special instructions for copying such records.
The concept of records and fields was central in some early file sorting and tabulating utilities, such as IBM's Report Program Generator (RPG).
COBOL was the first widespread programming language to support record types, and its record definition facilities were quite sophisticated at the time. The language allows for the definition of nested records with alphanumeric, integer, and fractional fields of arbitrary size and precision, as well as fields that automatically format any value assigned to them (e.g., insertion of currency signs, decimal points, and digit group separators). Each file is associated with a record variable where data is read into or written from. COBOL also provides a MOVE CORRESPONDING statement that assigns corresponding fields of two records according to their names.
The early languages developed for numeric computing, such as FORTRAN (up to FORTRAN IV) and Algol 60, did not have support for record types; but latter versions of those languages, such as Fortran 77 and Algol 68 did add them. The original Lisp programming language too was lacking records (except for the built-in cons cell), but its S-expressions provided an adequate surrogate. The Pascal programming language was one of the first languages to fully integrate record types with other basic types into a logically consistent type system. IBM's PL/1 programming language provided for COBOL-style records. The C programming language initially provided the record concept as a kind of template (struct) that could be laid on top of a memory area, rather than a true record data type. The latter were provided eventually (by the typedef declaration), but the two concepts are still distinct in the language. Most languages designed after Pascal (such as Ada, Modula, and Java) also supported records.
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