Why do we need CCoins in addition to CTransactions?


Bitcoin's very different things to different people, and obviously can't be everything to everyone. A lot of people really like a subset of its properties whilst disliking others. Some aspects of bitcoin are modifiable by comunity vote, some others not, and implementing yet others may require too much changes to the core code.

By allowing forks to be created, different ideas of what a crypto-currency can and maybe should be are competing directly against one another, in a Darwinian-like evolution.

Litecoin, for instance, tried to address 3 perceived problems with Bitcoin (others don't perceive them as problems or may even regard them as features): transactions taking too much to confirm, a "small" ceiling as to the max. number of currency to be mined, and a hash function that gives a very unfair advantage to users with GPUs and ASICs - theoretically this last one could mean mining will end-up, in the long term, concentrated in very few hands, besides making it...

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It's in fact a little more advanced than you imagine it. (So expect this answer to be a bit more in-depth.)

There is no such thing as an accounts "balance". It only exists implicitly.

When people make transactions, they actually create outputs for a certain amount of bitcoins. Using a special script language, the person making the transaction can specify the requirement for spending that output. There's a whole range of options you have to specify this.

The most common output script is something that holds the following condition "to spend this transaction, the spender must sign this hash with the private key from this address". So this basically means that the owner of that address can spend it. This are the type of outputs that you will probably generate when you "send money to an address". They are called pay-to-pubkey-hash transactions.

Other possible output scripts can be stupid things like "anyone can spend this" to very complex things like "at...

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I disagree with the premise of your question. In reality we have three forms of current now, not two. I'll explain that below, but first:

Historically, the only accepted money was valuable metals, primarily silver and gold (this was different in different societies -- some used seashells -- but to keep the discussion simple, we'll go with metals). Eventually, people figured out that they could turn these metals into standardized coins so they wouldn't have to spend valuable time weighing the metal each time they wanted to engage in a transaction. As economies grew, however, it became impractical to use coins because no one could carry around enough to cover the items that were being bought and sold. Imagine if a large business or a government had to pay for everything they bought with coins.

When that happened, people started using paper documents that would promise to deliver a certain amount of gold or silver upon demand. For instance, a one dollar bill could be taken to...

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Now that you have seen what transaction processing is, we need to look at why you would want to use it in developing your application. There were a number of reasons that became evident when looking at what transaction processing is. The ability to develop applications in a single-user mode, then use the transaction processing system to scale to hundreds or thousands of users is one reason. As a matter of course, the transaction processing system also provides the support for automatic rollback of transactions that did not complete successfully. There are other reasons for using transaction processing that become much more readily available to developers when working in a transaction processing system. These include the concepts of a three-tier application model, applications distributed across many systems, and the benefits of what is know as the ACID properties of transaction processing systems.

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Why Do We Need Transaction Processing?

Let’s examine an example, entering an invoice into an accounting system. When we create an invoice, several data files may be updated. The customer master file may have a field for each customer that keeps the current balance. This balance must be increased if we issue an invoice. There is an invoice file that has a record added to it. There may be a separate invoice detail file, keeping a record of each line on the invoice. In addition, each invoice detail will affect the balance of an inventory item. All of these files must be in sync - the customer balance must match the total of the open invoices, the detail lines must all be present, and the inventory balances must be accurate as affected by the invoices and other activities.

What happens if the computer crashes while these files are being updated? You could have some of the files already updated, but others not. For instance, the customer and invoice files could be...

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I don't think there's value in own many crypto-currencies, 3-4 max are worth it, the rest are just imitations.

I hold for some of the same reasons as you, investment value and such. But the reason they have demand to begin with (which is what drives the investment value we're seeking) is because it represents a monetary system that drastically improves upon the government-controlled, government-manipulated, perennially-inflating , middle-man requiring fiat currency we're all required to use.

The fact that almost any transaction I make with MY MONEY requires a middle-man to charge me a fee is enraging. I can't even get cash out of the bank without a fee from an ATM or spending time going to the damn bank!

This global monetary system can be improved to each person in control of their own money...and bitcoin is that improvement. It's...

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Accounting’s Importance to Business

So why do we need accounting? Asking that question of an accountant is like asking a farmer why we need rain. We need accounting because it’s the only way for business to grow and flourish. Accounting is the backbone of the business financial world. After all, accounting was created in response to the development of trade and commerce during the medieval times.

Italy is our first recorded source for accounting entries, and the first published accounting work in 1494 was by a Venetian monk. So you see accounting as an organized method for record-keeping has been around almost as long as the trade and business industries. Another interesting fact is the knowledge and principles upon which the first accounting practices were established, have changed very little in the many hundreds of years that accounting has been in use. The concepts of assets, liabilities, and income and the need to reconcile these areas is still the basis for all...

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Imagine that you’re implementing a system for a large bookstore. Many operations have to take place at the same time, multiple customers may simultaneously want to purchase the same book, prices of some books may change, new products are still being delivered, etc. As you know, a single action done by a user is run as a transaction in a database. Let's see what can happen if you allow multiple transactions to work on the same data.

For this example, we will work on the product table, which looks like this:

At first, the content of this table is:

Dirty Reads

Look at this sequence of operations:


What is happening here? Transaction 1 changes the price of “Effective Java.” Transaction 2 then read the new price of 90.00. But Transaction 1 is then rolled back: maybe the bookstore staff changed their mind, or maybe there was an error which prevented the transaction from being committed to the database. But...

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Dubner thinks we should do away with the penny.

A young economist I know, Patrick DeJarnette, believes a much more radical change in currency is warranted. Here is what Patrick writes:

Late one night I was curious how efficient the “penny, nickel, dime, quarter” system was, so I wrote a little script to compare all possible 4-coin systems, with the following stipulations:

1. Some combination of coins must reach every integer value in [0,99].
2. Probability of a transaction resulting in value v is uniform from [0,99].

In other words, you start with $10 and no coins. You buy something at the store. Afterward, the chance you have 43 cents in your pocket is equal to the probability that you have 29 or 99 cents in your pocket (in addition to any bills).

Requirement (1) implies the penny is necessary, as you must have a combination of coins that reach value = 1 cent.

With this in mind, the current combination of coins (penny, nickel, dime,...

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Probability can be represented numerically with a number between zero and one, with zero representing the impossibility of something specific happening and one representing the certainty of that thing happening. This number is often transferred to a percentage in order to predict something useful, such as a weather person predicting the likelihood of rain on the following day. Such an individual uses probability by taking available data on weather and making the most accurate prediction possible. Probability theory differs from statistics because statistics requires the examination of what has already occurred in order to determine how such a result occurred.

One frequent use of probability is the determination of events that are effectively impossible to quickly predict when a random determination needs to be made. This is commonly seen in sporting events in which a coin flip can influence aspects of the game. In truth, a coin flip can be influenced by factors such as coin...

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The Canadians are getting rid of their penny. Let them. Let's be smarter than they are and cling to ours like ivy on a garden wall.

Why? Because changing currency hurts consumers and it hurts the economy. It is always -- always -- an excuse to round up. Ask consumers in Australia, Sweden, Brazil, Finland, Israel and six other countries where small notes and coinage were taken out of circulation.

Ask especially in the United Kingdom, which last year "celebrated" its 40th anniversary of decimalization.

I mention this now because Canada's decision last week is sure to rekindle our own on-again-off-again kill-the-penny conversation. We've had a number of attempts in Washington in the last 10 years. It wouldn't surprise anyone if some member of Congress in search of an issue used Canada as a ramp into new legislation to do the penny in.

The alternative to the penny is rounding transactions to the nearest nickel. That will make goods and services more...

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A set which forms a matroid (https://en.wikipedia.org/wiki/Matroid) can be used to solve the coin changing problem by using greedy approach. In brief, a matroid is an ordered pair M = (S,l) satisfying the following conditions:

S is a finite nonempty set l is a nonempty family of subsets of S, called the independent subsets,such that if B->l and A is a subset of B, then A -> l If A-> l, B-> l and |A| < |B|, then there is some element x-> B-A such that A U {x} ->l

In our question of coin changing, S is a set of all the coins in decreasing order value We need to achieve a value of V by minimum number of coins in S

In our case, l is an independent set containing all the subsets such that the following holds for each subset: the summation of the values in them is B-A such that A U {x} ->l (According 3) So, {25,15} should belong to l, but its a contradiction since 25+15>30

So, S is not a matroid and hence greedy approach won't work on...

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Trustcoins are used to facilitate trust on the WeTrust network. Many of the things we take for granted in the modern world like loans, savings, and insurance, are only possible because of trust, and the blockchain is no different. In order for these types of services to work on the blockchain, there needs to be a token to compensate people who are providing a role as a trusted third party. It’s similar to how banks and insurance companies charge a fee to their customers for serving as a trusted party. Let’s take a look at an example to see how Trustcoins (or TRST) are used to compensate people for facilitating trust on the WeTrust network.

TRST are used by users of our Trusted Lending Circle platform to pay fees to the foreperson organizing the ROSCA. A foreperson is undertaking some degree of risk in organizing a ROSCA, to his or her reputation, or to his or her finances (if the foreperson promises to cover any funds not received in a given ROSCA...

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APThe global war on drugs began in 1961, when the UN Single Convention on Narcotic Drugs was established in order to create a "drug-free world."

The United Nations Office on Drugs and Crime puts out an annual "World Drug Report" wherein they examine trends in drug use and production. However, the report never cares to assess the costs created by the war on drugs itself, which are the real problem to begin with.

A new organization, Count the Costs, has decided it's time for an assessment. To this end, they have compiled a comprehensive report detailing the death and destruction the war on drugs has directly caused around the world over the past 50 years.

Unfortunately, as Count the Costs points out, the saddest effect of the war on drugs is that "the centrality of criminalizing users means that in reality a war on drugs is to a significant degree, a war on drug users – a war on people."

Click to see what's wrong with the war on drugs > » ...

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We all use cash - notes and coins - but with the increasing popularity of transacting by other methods, mobile phone, debit cards, do we still need cash? Some countries in northern Europe such as Sweden and Denmark are working towards a cashless society within the next 10 years. But what about those who are unable to open a bank account, the low waged, the homeless?

Although it is argued that getting rid of large amounts of cash would reduce both large and small scale crime, others argue that it is an inalienable right for a citizen to be anonymous, something that is impossible with a debit card or using mobile money which can be traced. Mike Williams asks is cash still king and if so why?

(Photo: Various world currency in a green money box. Credit:...

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