CIS133C CLASS 1

1. Instructor introduction
   Systems Analyst  at Consolidated Freightways Corp



2. Class information
   Syllabus including prerequisites, text, grading, and lab hours.
   Schedule including exam dates and due dates for lab assignments.



3. Student introductions from quiz 1



4. Introduction to COBOL
   
   THE PAST
   
   In the 1950’s, when computers were first used for problem solving, all programs were written in machine language. These instructions consist of a series of ones and zeros that represent on and off electrical states. But, coding in machine language is very time consuming (costly), it’s too easy for a human programmer to make a mistake, and machine language is machine dependent. The main reason for developing COBOL was to introduce a uniform, machine-independent computer programming language for business use.
   
   Grace Murray Hopper (1906-92) is known as the "mother of COBOL". She was an American mathematician and retired rear admiral in the United States Navy who first conceived of compilers. She developed the first commercial high-level programming language, called FLOW-MATIC a major forerunner of COBOL.
   
   COmmon Business-Oriented Language was first developed by the COnference of DAta SYstems Language (CODASYL) in 1960. It is a structured programming language.
   
   COBOL was originally developed with the first three main characteristics in mind; but there are additional features of COBOL ---
   1. machine independent - COBOL programs can be executed on many different types of computers w/little or no modification - AS400 to IBM, even PC to mainframe.
   2. easy to maintain - program maintenance is the process of making modifications to existing programs, most programming time is spent doing this, programs that are easiest to maintain will save time and money.
   3. self-documenting - the programming language instructions or code contain English-like words and phrases that pretty much spell out what the program is doing.
   4. uniquely organized - programs are divided into four standard parts called divisions.
   5. suited for commercial data processing - most business data processing requires input/output of large amounts of data and/or simple calculations.
   6. data is organized into records - each record contains a collection of data (example: one customer’s account number, name, address, balance owed, purchases, payments received).
   7. programs can process several different types of files - sequential, indexed sequential, relative.
   8. programs can read and write massive amounts of data using only a few statements.
   
   THE PRESENT
   
   Information managers are still hiring people with COBOL knowledge and experience. Businesses handle most of their routine data processing needs with computer programs written in COBOL.
   
   THE FUTURE
   
   Y2K and beyond
   
   
5. Introduction to structured programming
   
   Hardware costs used to be high compared to software costs but the reverse is true today. Most of the expense for developing computer programs goes to paying programmer salaries.
   
   To reduce software development costs it must be efficiently developed and software professionals have found that an efficient development process consists of four distinct phases. The first two phases are critical and time spent here will save time later.
   
   Program development lifecycle --
   
   1. Specification Phase - understand the purpose of the program and clearly define exactly what to do before proceeding with the programming task.
   2. Design Phase - plan what is to be done - analyze the program spec and determine how the input data will be converted into the output data - use standard tools for designing a program. Although the main processing is discussed in the program spec there will always be many details to be decided in the design phase. DO NOT SKIP THIS STEP.
   3. Coding Phase - converting a design into a computer program in COBOL. If the first two phases have been completed properly, the coding phase will proceed smoothly.
   4. Testing Phase - where all aspects of the program are tested to ensure that the program functions as intended.
   
   Program design tools will be discussed in a later class . . .
   -- Warnier/Orr
   -- Hierarchy or structure charts
   -- Flowcharts
   -- Pseudocode
   

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