STRUCTURE OF CARD:-
A credit card is a thin plastic
card, usually 3-1/8 inches by 2-1/8 inches in size, that contains
identification information such as a signature or picture, and authorizes the
person named on it to charge purchases or services to his account -- charges
for which he will be billed periodically. Today, the information on the card is
read by automated teller machines (ATMs), store readers, and bank and Internet
computers.
FRONT SIDE:-
Front side
of every card have a unique number. Although phone , gas and department stores
have their own numbering systems, ANSI Standard X4.13-1983 is the system
used by most national credit-card systems.
The front of your credit card
has a lot of numbers -- here's an example of what they might mean.
Some of the numbers stand for:
The first digit in your
credit-card number signifies the system :-
1. - travel/entertainment cards (such as American Express and Diners Club)
2. - Visa
3. - Master card
4. - Discover card
The
structure of the card number varies by system. For example, American Express
card numbers start with 37; Carte Blanche and Diners Club with 38.
1. American Express - Digits three and four are type and currency, digits five through 11 are the account number, digits 12 through 14 are the card number within the account and digit 15 is a check digit.
2. Visa - Digits two
through six are the bank number, digits seven through 12 or seven through 15
are the account number and digit 13 or 16 is a check digit.
3. MasterCard - Digits
two and three, two through four, two through five or two through six are the
bank number (depending on whether digit two is a 1, 2, 3 or other). The digits
after the bank number up through digit 15 are the account number, and digit 16
is a check digit.
BACK SIDE:-
The stripe
on the back of a credit card is a magnetic stripe, often called a magstripe.
The magstripe is made up of tiny iron based magnetic particles in a plastic-like
film. Each particle is really a tiny bar magnet about 20-millionths of an
inch long. Your card has a magstripe on the back and a place for your
all-important signature.The magstripe can be "written" because the
tiny bar magnets can be magnetized in either a north or south pole direction.
The magstripe on the back of the card is very similar to a piece of cassette
tape. A magstripe reader can understand the information on the three-track
stripe.
INFORMATION ON THE STRIPE:-
There are three tracks on
the magstripe. Each track is about one-tenth of an inch wide. The ISO/IEC
standard 7811, which is used by banks, specifies:-
Track one is 210 bits per inch (bpi), and holds 79 6-bit plus parity bit read-only characters.
Track two is 75 bpi, and holds 40 4-bit plus
parity bit characters.
Track three is 210 bpi, and holds 107 4-bit
plus parity bit characters.
Your credit
card typically uses only tracks one and two.Track three is a read/write track
(which includes an encrypted PIN, country code, currency units and amount
authorized), but its usage is not standardized among banks.
The information on track one is contained in two formats: A, which is reserved for proprietary use of the card issuer, and B, which includes the following:
Start sentinel - one character
Format code="B" - one character (alpha only)
Primary account number - up to 19 characters
· Separator - one
character
Country code - three characters
Name - two to 26 characters
Separator - one character
Expiration date or separator - four characters or one character
Discretionary data - enough characters to fill out maximum record
length (79 characters total)
End sentinel - one character
Longitudinal
redundancy check (LRC) - one character
LRC is a form of
computed check character.
The format for track
two, developed by the banking industry, is as follows:
Start sentinel - one character
Primary account number - up to 19 characters
Separator - one character
Country code - three characters
Expiration date or separator - four characters or one character
Discretionary data - enough characters to fill out maximum record
length (40 characters total)
LRC
- one character
If the ATM isn't accepting your card,
your problem is probably either:
1.
A dirty or scratched magstripe
2. An erased magstripe (The
most common causes for erased magstripes are exposure to magnets)
NEXT COMING:::TYPES OF CARDS, ATM CARD VS CHECK CARD,E-ZPASS WORKING PROCESSTYPES OF CARDS
