The document discusses different types of computer programming languages including low-level languages like machine language and assembly language that are closer to hardware, and high-level languages like C++, Java, and Python that are easier for humans to read and write. It also covers basic programming concepts like variables, strings, statements, operators, and operands.

1. Computer Languages
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2. Computer programming language
Programming languages are used for expressing a
set of detailed instructions for a digital computer.
Such instructions can be executed directly when
they are in the computer manufacturer-specific
numerical form known as machine language, after a
simple substitution process when expressed in a
corresponding assembly language, or after
translation from some “higher-level” language.

4. Assembly language
Assembly language is one level
above machine language. It uses
short mnemonic codes for instructions and allows
the programmer to introduce names for blocks of
memory that hold data. One might thus write “add
pay, total” instead of “0110101100101000” for an
instruction that adds two numbers.

5. Machine language
 The numeric codes for the operations that a particular computer can
execute directly. The codes are strings of 0s and 1s, or binary
digits (“bits”), which are frequently converted both from and to
hexadecimal (base 16) for human viewing and modification. Machine
language instructions typically use some bits to represent operations,
such as addition, and some to represent operands, or perhaps the
location of the next instruction. Machine language is difficult to read
and write, since it does not resemble conventional mathematical
notation or human language, and its codes vary from computer to
computer.

6. High level languages
 High level languages are written in a form that is close to our
human language, enabling to programmer to just focus on the
problem being solved.
 No particular knowledge of the hardware is needed as high level
languages create programs that are portable and not tied to a
particular computer or microchip.
 Examples include: C++, Java, Pascal, Python, Visual Basic.

7. Low level languages
Low level languages are used to write programs that
relate to the specific architecture and hardware of a
particular type of computer.
They are closer to the native language of a computer
(binary), making them harder for programmers to
understand.
Examples of low level language:
Assembly Language, Machine Code

8. High Level Language Low Level Language
1. It is programmer friendly language. It is a machine friendly language.
2.
High level language is less memory
efficient. Low level language is high memory efficient.
3. It is easy to understand. It is tough to understand.
4. It is simple to debug. It is complex to debug comparatively.
5. It is simple to maintain. It is complex to maintain comparatively.
6. It is portable. It is non-portable.

9. COBOL
 COBOL (COmmon Business Oriented Language) was developed in the late
1950s by computer manufacturers, the U.S. government and industrial computer
users. COBOL is used for commercial applications that require precise and
efficient manipulation of large amounts of data. Much business software is still
programmed in COBOL.

10. FORTRAN
 The first important algorithmic language was FORTRAN (formula
translation), designed in 1957 by an IBM team led by John Backus. It
was intended for scientific computations with real numbers and
collections of them organized as one- or multidimensional arrays. Its
control structures included conditional IF statements, repetitive loops
(so-called DO loops), and a GOTO statement that allowed
nonsequential execution of program code. FORTRAN made it
convenient to have subprograms for common mathematical
operations, and built libraries of them.
 FORTRAN was also designed to translate into efficient machine
language. It was immediately successful and continues to evolve.

11. BASIC
 BASIC (beginner’s all-purpose symbolic instruction code) was
designed at Dartmouth College in the mid-1960s by John Kemeny and
Thomas Kurtz. It was intended to be easy to learn by novices,
particularly non-computer science majors, and to run well on a time-
sharing computer with many users. It had simple data structures and
notation and it was interpreted: a BASIC program was translated line-
by-line and executed as it was translated, which made it easy to locate
programming errors.
 Its small size and simplicity also made BASIC a popular language for
early personal computers. Its recent forms have adopted many of the
data and control structures of other contemporary languages, which
makes it more powerful but less convenient for beginners.

12. Java
 In the early 1990s, Java was designed by Sun Microsystems, Inc., as a
programming language for the World Wide Web (WWW). Although it
resembled C++ in appearance, it was fully object-oriented. In
particular, Java dispensed with lower-level features, including the
ability to manipulate data addresses, a capability that is neither
desirable nor useful in programs for distributed systems. In order to be
portable, Java programs are translated by a Java Virtual Machine
specific to each computer platform, which then executes the Java
program. In addition to adding interactive capabilities to the Internet
through Web “applets,” Java has been widely used for programming
small and portable devices, such as mobile telephones.

13. C
 C, computer programming language developed in the early 1970s by
American computer scientist Dennis M. Ritchie at Bell Laboratories (formerly
AT&T Bell Laboratories).
 C was designed as a minimalist language to be used in writing operating
systems for minicomputers, such as the DEC PDP 7, which had very limited
memories compared with the mainframe computers of the period.
 The language was devised during 1969–73, alongside the early development
of the UNIX operating system. It was based on CPL (Combined Programming
Language), which had been first condensed into the B programming
language—a stripped-down computer programming language—created in
1969–70 by Ken Thompson, an American computer scientist and a colleague
of Ritchie. Ritchie subsequently rewrote and restored features from CPL to
create C, eventually rewriting the UNIX operating system in the new
language.

14. Variables
 Variables are used to store information to be referenced and manipulated in a computer program.
They also provide a way of labeling data with a descriptive name, so our programs can be understood
more clearly by the reader and ourselves. It is helpful to think of variables as containers that hold
information. Their sole purpose is to label and store data in memory. This data can then be used
throughout your program.
 For example, assume you want to store two values 10 and 20 in your program and at a later stage,
you want to use these two values. Let's see how you will do it. Here are the following three simple
steps −
 Create variables with appropriate names.
 Store your values in those two variables.
 Retrieve and use the stored values from the variables.
 Creating variables
 Creating variables is also called declaring variables in C programming. Different programming
languages have different ways of creating variables inside a program. For example, C programming
has the following simple way of creating variables −

15. Variables
 #include <stdio.h>
 int main() {
 int a;
 int b;
 The above program creates two variables to reserve two memory
locations with names a and b. We created these variables
using int keyword to specify variable data type which means we want
to store integer values in these two variables.

16. Character
Every letter, digit, and punctuation mark is
a character. There are also many characters
that are invisible on screen, such as
the space, tab, and carriage-return characters.

17. Strings
The technical description of a String is: an
array of characters. The informal view of a
string is a sentence. Strings are almost always
written in code as a quoted sequence of
characters, i.e., "this is a string".

18. String
Most programming languages have a data type called a string,
which is used for data values that are made up of ordered
sequences of characters, such as "hello world". A string can
contain any sequence of characters, visible or invisible, and
characters may be repeated. The number of characters in the
string is called its length, and "hello world" has length 11 - made
up of 10 letters and 1 space. There is usually a restriction on the
maximum length of a string. There is also such a thing as
an empty string, which contains no characters - length 0.
A string can be a constant or variable. If it is a constant, it is
usually written as a sequence of characters enclosed in single or
double quotation marks, ie 'hello' or "hello".

19. Statement
 Most programming languages have the concept of a statement.
A statement is a command that the programmer gives to the computer. For
example:
 print "Hello, world!"
 This command has a verb (“print”) and other details (what to print). In this
case, the command print means “show on the screen,” not “print on the
printer.” The programmer either gives the statement directly to the computer
(by typing it while launching a special program), or creates a text file with the
command in it. You could create a file called “hi.txt” using a program like
Notepad, put the above command in it, and give the file to the computer.

20. Statement
 An instruction written in a high-level language. A statement directs the
computer to perform a specified action. A single statement in a high-
level language can represent several machine-language instructions.
Programs consist of statements and expressions. An expression is a
group of symbols that represent a value.

21. Operators and operands
 Operators are special symbols that represent computations like addition and multiplication.
The values the operator uses are called operands.
 The following are all legal Python expressions whose meaning is more or less clear:
 20+32 hour-1 hour*60+minute minute/60 5**2 (5+9)*(15-7)
 The symbols +, -, and /, and the use of parenthesis for grouping, mean in Python what they
mean in mathematics. The asterisk (*) is the symbol for multiplication, and ** is the symbol for
exponentiation.
 When a variable name appears in the place of an operand, it is replaced with its value before
the operation is performed.