# Payments

For submitting a manuscript for review and purchases, we accept payments in **fiat** BRL, EUR, USD **and** **digital** currencies such as USDC, DAI, ETH and BTC.&#x20;

Certain payment methods may be unavailable in the initial release (Version 1) of our platform. We will introduce additional payment methods and ensure that payments are processed swiftly as we continue to enhance our payment gateways.

**Fiat currencies** are a type of currency that has value because a government has declared it to be legal tender within its jurisdiction. Use your credit card to make your payment.

**Digital currencies**, often referred to as cryptocurrencies, are a type of currency that exists in digital form and relies on cryptographic techniques to secure and verify transactions.

**To engage in digital currency transactions, you must possess a digital wallet.**&#x20;

[Metamask](https://metamask.io) stands out as one of the most widely used digital wallets. To get started, simply visit Metamask's [website](https://metamask.io) and create your account.

**Fiat currencies** are not backed by a physical commodity like gold or silver; instead, their value is derived from the trust and confidence of the people who use them and the government that issues them. Fiat currencies are the most common form of currency in the world today and are typically used for everyday transactions, including buying goods and services. They are not redeemable for a fixed quantity of any physical asset, and their value can fluctuate based on various economic factors, including inflation, interest rates, and government policies. Examples of fiat currencies include the United States dollar (USD), the Euro (EUR), the Japanese yen (JPY), and many others.

Unlike traditional fiat currencies, **digital currencies** are decentralized and typically not issued or controlled by any central authority, such as a government or central bank. Instead, they operate on decentralized ledger technology called blockchain.

Key characteristics of digital currencies include:

1. Decentralization: Digital currencies are not controlled by a central authority or government. They operate on distributed ledger technology, which is maintained by a network of nodes (computers) participating in the network.
2. Cryptography: Transactions in digital currencies are secured and verified using cryptographic techniques. This ensures the integrity and security of the currency and its transactions.
3. Transparency: Most digital currencies use blockchain technology, which records all transactions in a public ledger. This ledger is transparent and accessible to anyone, providing a transparent and immutable history of transactions.
4. Anonymity: While digital currency transactions are recorded in a public ledger, the identities of the parties involved are often pseudonymous or can be kept private, depending on the specific cryptocurrency.
5. Borderless: Digital currencies can be transferred and received across borders without the need for intermediaries, like banks or currency exchange services. This can make international transactions faster and more cost-effective.
6. Limited supply: Many digital currencies have a predefined supply limit, meaning there is a maximum number of coins or tokens that can ever be created. This scarcity can impact their value and is often associated with concepts like Bitcoin's halving.

Some well-known digital currencies include USDC, Bitcoin (BTC) and Ethereum (ETH). Digital currencies have gained popularity for their potential as an alternative store of value, a medium of exchange, and for enabling innovative financial applications through smart contracts and decentralized platforms. However, they are also associated with price volatility and regulatory challenges in many jurisdictions.

A cryptocurrency wallet, often referred to as a crypto wallet, is a digital tool that allows users to securely store, manage, and interact with their cryptocurrencies. Cryptocurrencies exist only in digital form, and a crypto wallet serves as the equivalent of a digital bank account, enabling users to send, receive, and manage their crypto assets. These wallets use cryptographic techniques to ensure the security of transactions and the protection of private keys, which are essential for accessing and managing cryptocurrency holdings.

There are two primary types of cryptocurrency wallets:

1. **Software Wallets**:
   * **Online Wallets**: These wallets are cloud-based and accessible through web browsers or mobile apps. They are convenient but may be more susceptible to security risks.
   * **Mobile Wallets**: Designed for mobile devices, these wallets can be installed as apps. They are suitable for users who need to manage their cryptocurrencies on the go.
   * **Desktop Wallets**: Installed on a user's computer, desktop wallets provide more control over security. They are considered more secure than online wallets.
   * **Web Wallets**: These are online wallets accessed through a web browser. They offer a balance between convenience and security.
2. **Hardware Wallets**:
   * These are physical devices specifically designed for storing cryptocurrencies offline. Hardware wallets are considered one of the most secure options because they are not connected to the internet, making it difficult for hackers to access the private keys.

Key functions and features of cryptographic digital wallets include:

* **Storage**: Crypto wallets store the private keys that allow users to access and manage their cryptocurrency holdings. These keys must be kept secure, as they are the keys to the digital vault.
* **Security**: Security is a critical aspect of crypto wallets. They employ various encryption and authentication measures to protect private keys and the user's assets.
* **Transaction Management**: Users can send and receive cryptocurrencies through their wallets. They can specify recipient addresses and the amount they want to send.
* **Balances and Transaction History**: Crypto wallets display the user's cryptocurrency balances and transaction history, allowing them to monitor their holdings and activities.
* **Compatibility**: Different wallets support various cryptocurrencies. Some wallets are multi-currency wallets, allowing users to manage multiple cryptocurrencies in one place.
* **Backup and Recovery**: Many crypto wallets provide backup and recovery options to ensure that users can regain access to their assets in case of device loss or failure.

It's important to choose a crypto wallet that aligns with your security preferences and the type of cryptocurrencies you intend to store. Security practices, such as keeping private keys secure and regularly updating software, are essential for protecting your digital assets.

