Important Short Notes on Information Technology in Financial Services_DAIBB (Paper-4)
ASCII
The
American Standard Code for Information Interchange is a character-encoding
scheme originally based on the English alphabet. ASCII codes represent text in
computers, communications equipment, and other devices that use text. Most
modern character-encoding schemes are based on ASCII, though they support many
additional characters. It was only developed for communication and first
adopted in 1963.
ASCII
has been very popular in the computer world. It
contains seven bits to define each letter or character excluding eighth
bit for error-checking function. There are 128 specific characters including
capital letters, small letters, 0 to 9 digit, special symbols and some specific
character having specific different functions.
Thirty-three codes are used to
represent things other than specific characters. The first 32 (0-31) codes
represent a chime sound, used to
feed line as well as to start of a
header. The final code, 127 represents a backspace while the first 31 bits are
the printable characters. Bits ranging from
48 to 57 represent the numeric digits and 65 to 90 represents the capital letters, while bits 97
to 122 are the lower-case letters. The rest bits represent symbols of
punctuation, mathematical symbols, and other symbols such as the pipe and
tilde.
Earlier
ASCII was developed only in six bits for
a simpler character set. But finally it
has been reconstructed using seven bits for assimilating lower-case letters, punctuation, and control
character sets to enhance its utility.
No other than English characters has
been used in ASCII. ASCII is not used in IBM computers. IBM has its own
built-in-code called EBCDIC code containing 256 character sets. Nowadays
Unicode character set is replacing ASCII code very rapidly. ASCII is being
famous in ASCII art phase that describes the use of the basic character set to
create visual approximations of images.
'Personal Identification Number - PIN'
A
personal identification number is a secret numeric password shared between a
user and a system that can be used to authenticate the user to the system.
Typically, the user is required to provide a non-confidential user identifier
or token (the user ID) and a confidential PIN to gain access to the system.
Upon receiving the user ID and PIN, the system looks up the PIN based upon the
user ID and compares the looked-up PIN with the received PIN. The user is
granted access only when the number entered matches with the number stored in
the system. Hence, despite the name, a PIN does not personally identify the
user.
PINs
are most often used for automated teller machines (ATMs) but are increasingly
used at the point of sale, for debit cards and credit cards. For example, when
you take money out of an ATM, you enter your PIN number to prove that you're
authorized to make the withdrawal. You might also enter a PIN number if you use
your debit card at a retailer (only for POS transactions, not signature
transactions).
UPS
Short
for uninterruptible power supply, a power supply that includes a battery to
maintain power in the event of a power outage. Typically, a UPS keeps a
computer running for several minutes after a power outage, enabling you to save
data that is in RAM and shut down the computer gracefully. Many UPSs now offer
a software component that enables you to automate backup and shut down
procedures in case there's a power failure while you're away from the computer.
There
are two basic types of UPS systems: standby power systems (SPSs) and on-line
UPS systems. An SPS monitors the power line and switches to battery power as
soon as it detects a problem. The switch to battery, however, can require
several milliseconds, during which time the computer is not receiving any
power. Standby Power Systems are sometimes called Line-interactive UPSes.
An
on-line UPS avoids these momentary power lapses by constantly providing power
from its own inverter, even when the power line is functioning properly. In
general, on-line UPSs are much more expensive than SPSs.
A
UPS is typically used to protect computers, data centers, telecommunication
equipment or other electrical equipment where an unexpected power disruption
could cause injuries, fatalities, serious business disruption or data loss. UPS
units range in size from units designed to protect a single computer without a
video monitor (around 200 VA rating) to large units powering entire data
centers or buildings
RDBMS
RDBMS
stands for Relational Database Management System. RDBMS data is structured in
database tables, fields and records. Each RDBMS table consists of database
table rows. Each database table row consists of one or more database table
fields. An important feature of relational systems is that a single database
can be spread across several tables. This differs from flat-file databases, in
which each database is self-contained in a single table.
RDBMS
store the data into collection of tables, which might be related by common
fields (database table columns). RDBMS also provide relational operators to
manipulate the data stored into the database tables. Most RDBMS use SQL as
database query language.
Relational
database management system (DBMS) stores data in the form of related tables.
Relational databases are powerful because they require few assumptions about
how data is related or how it will be extracted from the database. As a result,
the same database can be viewed in many different ways.
RAM
RAM
is an acronym for random access memory, a type of computer memory that can be
accessed randomly; any byte of memory can be accessed without touching the
preceding bytes. RAM is the most common type of memory found in computers and
other devices, such as printers.
RAM
is a temporary storage for data. For instance, when you open Microsoft Word (or
any program), it goes into RAM because your CPU can get it a lot faster from
RAM, than if it tried to get it off of your hard drive. However, RAM is dynamic
which means if the power is cut off then any data that is in RAM is lost. Let’s
say you are typing a letter, each time you hit the keyboard that data is put
into RAM until it can be transferred to your hard drive. If the power goes off
then whatever is in RAM while you were typing will be lost.
In
common usage, the term RAM is synonymous with main memory, the memory available
to programs. For example, a computer with 8MB RAM has approximately 8 million
bytes of memory that programs can use. In contrast, ROM (read-only memory)
refers to special memory used to store programs that boot the computer and
perform diagnostics. Most personal computers have a small amount of ROM (a few
thousand bytes). In fact, both types of memory (ROM and RAM) allow random
access. To be precise, therefore, RAM should be referred to as read/write RAM
and ROM as read-only RAM.
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