The 1950s and early 1960s saw the emergence of two high-
level computer languages into widespread use. The first was
designed to be an efficient language for performing scien-
tific calculations .The second was designed
for business applications, with an emphasis on data pro-
cessing .However many programs continued to
be coded in low-level languages designed
to take advantages of the hardware features of particular
machines.
In order to be able to easily express and share meth-
ods of calculation .leading programmers
began to seek a “universal” programming language that
was not designed for a particular application or hardware
platform. By 1957, the German GAMM (Gesellschaft für
angewandte Mathematik und Mechanik) and the American
ACM (Association for Computing Machinery) had joined
forces to develop the specifications for such a language. The
result became known as the Zurich Report or Algol-58, and
it was refined into the first widespread implementation of
the language, Algol-60.
Language Features
Algol is a block-structured, procedural language. Each vari-
able is declared to belong to one of a small number of kinds
of data including integer, real number,
or a series of values of either type . While the
number of types is limited and there is no facility for defin-
ing new types, the compiler’s type checking (making sure a
data item matches the variable’s declared type) introduced a
level of security not found in most earlier languages.
An Algol program can contain a number of separate
procedures or incorporate externally defined procedures
and the variables with the same
name in different procedure blocks do not interfere with
one another. A procedure can call itself
Standard control structures were provided.
The following simple Algol program stores the numbers
from 1 to 10 in an array while adding them up, then prints
the total:
begin
integer array ints[1:10];
integer counter, total;
total := 0;
for counter :=1 step 1 until counter > 10
do
begin
ints [counter] := counter;
total := total + ints[counter];
end;
printstring “The total is:”;
printint (total);
end
Algol’s Legacy
The revision that became known as Algol-68 expanded
the variety of data types (including the addition of bool-
ean, or true/false values) and added user-defined types
and “structs” (records containing fields of different types
of data). Pointers (references to values) were also imple-
mented, and flexibility was added to the parameters that
could be passed to and from procedures.
Although Algol was used as a production language in
some computer centers (particularly in Europe), its rela-
tive complexity and unfamiliarity impeded its acceptance,
as did the widespread corporate backing for the rival lan-
guages FORTRAN and especially COBOL. Algol achieved
its greatest success in two respects: for a time it became
the language of choice for describing new algorithms for
computer scientists, and its structural features would be
adopted in the new procedural languages that emerged in
3 comments:
Nice post, thanks for sharing! Also check PlayBox HD Download
Get the best IT administration from managed it services va. This blog is important we adjust new contemplations. This blog containing some idea on innovation.
Nice Article, Keep it up!
Get Daily Latest Technology News, Guides, Free Registered Softwares & Tips and Tricks => Technology News
Post a Comment