Page 174 - DCAP507_SYSTEM_SOFTWARE

System Software

Notes  A variable is an identifier, which refers to computer memory space where some value can
be stored.

 A pointer is a variable that points at, or refers to, another variable. That is, if we have a
pointer variable of type ``pointer to int,`` it might point to the int variable i, or to the third
cell of the int array a.

 Labels are mainly used with a statement, so that the statement can be referenced in future
during the execution.

10.8 Keywords

Data Type: The kind of data that variables may hold is called as Data type.

High Level Language: High level languages basically consist of English like instructions rather
than mnemonic codes or binary digits of specific computer, so this language is easier to learn
than assembly language.
Labels: Labels are mainly used with a statement, so that the statement can be referenced in future
during the execution.
Pointer: A pointer is a variable that points at, or refers to, another variable. That is, if we have a
pointer variable of type ``pointer to int,`` it might point to the int variable i, or to the third cell
of the int array a.
Variable: A variable is an identifier, which refers to computer memory space where some value
can be stored.

10.9 Review Questions

1. Give two instances of programming where you will prefer a high level language over a
low level language.
2. What are high level languages? Illustrate the Importance of high level languages.

3. Discuss some popular high level programming languages.
4. Enlighten the various features of high level languages.
5. List the various data types. Enumerate with example.

6. What are User-defined Data Types? Illustrate different User-defined Data Types.
7. A programmer must own a practiced knowledge of a programming language data structure
so as to fully discover all of the properties of the language in the execution of an application.
Comment.
8. Explicate the concept of storage allocation with example.
9. Illustrate the process of accessing of pointers with examples.

10. Make distinction between Enumerated Data Type and subrange data type.
Answers: Self Assessment

1. programming language 2. low level/lowest level languages
3. machine 4. FORTRAN
5. Data type 6. enumerated

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