Pascal is an ALGOL-derived language developed by Niklaus Wirth of ETH to help teach students good programming habits. In the mid 1970s, as Wirth was developing Pascal, most students were learning FORTRAN and COBOL, both of which contain constructs that can be abused very easily. The idea was to teach students the structured programming ideals that make for good programming development style: encapsulated through the use of blocks that incorporated subsidiary procedures, the use of IF-THEN-ELSE and loop structures without the use of GOTO. It is probably the closest to ALGOL itself of the ALGOL- derived languages that saw common usage.
Pascal gained popularity in the United States largely through the development of the p-system ( which translated Pascal into an intermediate code called p-code) and their compiler which was available for a wide array of computers. But it exploded in popularity when Phillipe Kahn developed the Turbo Pascal compiler and started Borland International.
Standard Pascal lacked a strings type (which Borland corrected) and had a somewhat clumsy mechanism to access binary files (also corrected by Borland),r but the syntax is so crystal clear that it is almost impossible for anyone not to be able to read a Pascal program if they know anything about programming.
You will find below links to three examples which show you how to code basic constructs in Pascal: