The initial block download (IBD) is the process of building the complete Bitcoin blockchain from scratch. When a new node is configured and joins the network, it connects to other nodes and requests blocks from them. The new node processes these blocks and builds the blockchain until it catches up and is synchronized with the network.

When starting IBD, a node first gathers all the block headers from other nodes and then requests each complete block. This is done to increase efficiency and allow users to start using your node earlier.

While building the blockchain block by block, a Bitcoin node also builds the UTXO set, the complete list of all valid bitcoins.

This process may take a few days or a few weeks, depending on the Internet bandwidth and the specifications of the computer, since the current size of the entire blockchain is approximately 600 GigaBytes.

dbcache is mainly a write buffer and prevents you from needing to regularly write the current state of the UTXO set to disk. The dbcache parameter specifies how much memory the Bitcoin Core client can use for caching.

This can mean an improvement in performance when synchronizing many blocks because it avoids having to perform a lot of disk operations that are relatively slow.

There is a debate about whether this really helps the synchronization of the blockchain to be faster or not, this together with other factors such as a Moderna SSD and a good bandwidth in the connection.

To date there is a group of Bitcoiner indicating that dbcache is not mainly used as a (read) cache and it makes no difference to modify it.

COLDCARD MK4 is called the ultra-secure hardware wallet designed exclusively for Bitcoin. Originally from Toronto, Canada, manufactured by Coinkite in 2013.

Despite being classified as the safest, it may not be the best option for beginners, due to its complexity. Its lack of touch screen makes it more accurate but less intuitive.

It has an impressive array of security features, including dual security elements from different chip manufacturers. At first the firmware of the COLDCARD Mk4 was open source and then it became "verifiable source code".

✅ It has an NFC chip, it has a microSD slot all designed to complete PSBT.

✅ Multiple protection elements against attacks of any kind: coercion pin, two-word protection, brick pin.

❌ Extremely complex to use for a user with little experience.

Bitcoin Fear and Greed Index makes an assessment of the dominant mood in the market, so the psychological factor is also taken into account. It does this by taking into account the following factors:

Volatility (25%), Market Momentum/volume (25%), Social Media (15%), Surveys (15%), Dominance (10%), Trends (10%)

Extreme fear can be a sign that investors are too worried. That could be a buying opportunity.

When investors get too greedy, that means the market must suffer a correction.

We see all this in a simple meter from 0 to 100. Zero means "extreme fear," while 100 means "extreme greed."

Rust is a programming language designed by the Linux Foundation, the reason for its creation was the intention to have a safe replacement for the well-known C and C++ languages. It is an open source language, in which the community can contribute, discuss and share knowledge and ideas.

According to Rust experts, they have a much shorter learning curve than C++. It also has the advantage that they include controls in their design to prevent programming errors. It could be said that in addition to being easier to master, they take care of the developer from making mistakes.

Rust's inherent suitability for creating Bitcoin wallets is a result of its memory security, which makes Bitcoin wallets more robust and resistant to attacks.