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ComPonent-oriented develoPment and assemblY
Fortran-I-based software systems developed in the 1950s could not use any
software component, not even in the source code form for this reason. When Fortran
II was introduced in 1958, the concept of a subprogram was introduced. e subpro-
gram could be either a function or a subroutine. Subprograms are reused by many
main programs through function or subroutine invocations. us, Fortran II-based
software systems employed subprogram-based source code components. Fortran II
also provided support for independent compilation of a subprogram. erefore, the
subprogram could be used as a static binary component as well.
In 1960, Algol-60 was released, which introduced the block structure concept.
e block ...