Must I provide a Social Security number to any business or government agency that asks?

The Social Security number was originally devised to keep an accurate record of each individual’s earnings, and to subsequently monitor benefits paid under the Social Security program. However, use of the Social Security number as a general identifier has grown to the point where it is the most commonly used and convenient identifier for all types of record-keeping systems in the United States.

Specific laws require a person to provide his or her Social Security number for certain purposes. While we cannot give you a comprehensive list of all situations where a Social Security number might be required or requested, a Social Security number is required or requested by the following organizations:

·         Internal Revenue Service for tax returns and federal loans;

·         Employers for wage and tax reporting purposes;

·         Employers enrolled in E-Verify;

·         States for the school lunch program;

·         Banks for monetary transactions;

·         Veterans Administration as a hospital admission number;

·         Department of Labor for workers’ compensation;

·         Department of Education for Student Loans;

·         States to administer any tax, general public assistance, motor vehicle or drivers license law within its jurisdiction;

·         States for child support enforcement;

·         States for commercial drivers’ licenses;

·         States for Food Stamps;

·         States for Medicaid;

·         States for Unemployment Compensation;

·         States for Temporary Assistance to Needy Families; or

·         U.S. Treasury for U.S. Savings Bonds

The Privacy Act regulates the use of Social Security numbers by government agencies. When a federal, state, or local government agency asks an individual to disclose his or her Social Security number, the Privacy Act requires the agency to inform the person of the following: the statutory or other authority for requesting the information; whether disclosure is mandatory or voluntary; what uses will be made of the information; and the consequences, if any, of failure to provide the information.

If a business or other enterprise asks you for your Social Security number, you can refuse to give it. However, that may mean doing without the purchase or service for which your number was requested. For example, utility companies and other services ask for a Social Security number, but do not need it; they can do a credit check or identify the person in their records by alternative means.

Giving your Social Security number is voluntary, even when you are asked for the number directly. If requested, you should ask why your Social Security number is needed, how your number will be used, what law requires you to give your number and what the consequences are if you refuse. The answers to these questions can help you decide if you want to give your Social Security number. The decision is yours.

from the social security government site -- see the link below.
http://ssa-custhelp.ssa.gov/app/answers/detail/a_id/78/~/legal-requirements-to-provide-your-social-security-number

From the site makeuseof.com

Tip of the Day: Unfortunately, social security numbers aren't random either -- existing numbers can be somewhat predictable. However, the US Social Security Administration started assigning random numbers in June. Remember that SSNs aren't meant to be used for identification -- you're generally not obligated to provide your SSN if you're asked for it by a business

Credit Card Numbers Are Not Random: How To Read & Understand Them Yourself by Angela Alcorn

You may have heard before that credit card numbers follow a certain pattern and structure so that they can be validated before a transaction is accepted. However, it's one thing to know that the structure is there and another thing entirely to understand how credit card numbers work.

Why would this knowledge be useful? Well, if you run a small business that doesn't process credit card payments immediately, you could save yourself money by ensuring the card details are valid. If you don't, well it could still be fun to show off your skills at parties. Here's how you do it.

Learning Where The Numbers Come From Credit card numbers are not random. There's a special set of numbers to show information about the card issuer and another set to show information about the card holder. One other number is also important, but we'll come to that later.

The very first number is the Major Industry Identifier (MII) and it tells you what sort of institution issued the card.

• 1 and 2 are issued by airlines.
• 3 is issued by travel and entertainment.
• 4 and 5 are issued by banking and financial institutions.
• 6 is issued by merchandising and banking.
• 7 is issued by petroleum companies.
• 8 is issued by telecommunications companies.
• 9 is issued by national assignment.

The first six digits are the Issuer Identification Number (IIN). These can be used to look up where the card originated from. If you have access to a list that details who owns each IIN, such as this list of popular IINs on Wikipedia, you can see who issued the card just by reading the card number.

Here's a few you might recognise:

• Visa: 4*****
• American Express (AMEX): 34**** or 37****
• Diner's Club International: 36****
• Mastercard: 51**** to 55****

The seventh digit to the second-to-last digit is the customer account number. Most companies use just 9 digits for the account numbers, but it's possible to use up to 12. This means that using the current algorithm for credit cards, the world can issue about a trillion cards before needing to change the system.



We often see 16-digit credit card numbers today, but it's possible for a card issuer to issue a card with up to 19 digits using the current system. In the future, we may see longer numbers becoming more common.

The very last digit of each credit card is the check digit, or checksum. It is used to validate the credit card number using the Luhn algorithm, which we will now explain in detail.

The Luhn Algorithm Validation Check The Luhn Algorithm is used to validate all sorts of numbers, including credit cards, IMEI numbers and some social security numbers. It's not designed to be a cryptographically secure hash function, but merely a way to check errors are not made when recording numbers. It is not foolproof, but is generally considered to be useful.

Take the credit card number and read the digits from the right. Double every other number and write them down - if you do it in the same order as your card is written it will help with clarity. Now, wherever you have calculated a double-digit number, change it so that it reads as "first digit + second digit" (in other words, sum the digits of the products). Finally, take your calculations and add those numbers to the numbers remaining on your card that you didn't double. A legitimate credit card number will give you a result that is divisible by 10.

For instance, let's use a number I've just made up: 4634 8932 1298 2767. I'll enter it into a table to make it easier to understand the steps.

Try it yourself using the card from the picture earlier in this article. What can you learn from it?

"Allah be praised! I've invented the Zero!"
"What was that?"
"Oh, nothing.

Biology is the only science in which multiplication means the same thing as division.

<ba dum>