Key Characteristics and Concepts:

[Mitu100@]

Block Height: This refers to the number of blocks that have been mined since the first block (the "genesis block," which is Block 0).
As of May 21, 2025, the current Bitcoin block height is approximately 893,900 to 894,000.
Block Time: The Bitcoin protocol aims for an average block time of approximately 10 minutes. This is controlled by the difficulty adjustment.
Block Size Limit: Originally, Bitcoin blocks had a hospitals email list strict 1 MB size limit. However, with the implementation of Segregated Witness (SegWit) in 2017, the effective block size can be larger, often reaching around 2-4 MB in practice. This is because SegWit separates certain transaction data (witness data) which is then "weighted" differently, allowing more transactions to fit into a block while adhering to a "block weight" limit (4 million weight units) rather than a strict byte size.

Block Reward and Halving: The block reward (newly minted BTC given to the miner) halves approximately every four years (or every 210,000 blocks). This "halving" event reduces the supply of new Bitcoins, contributing to its scarcity. The most recent halving occurred in April 2024, reducing the reward from 6.25 BTC to 3.125 BTC per block.

Confirmations: When your transaction is included in a block, it has "1 confirmation." As subsequent blocks are added on top of that block, your transaction gains more confirmations. The more confirmations, the more secure and irreversible the transaction is considered (e.g., 6 confirmations is often considered a standard for high-value transactions).

Orphan Blocks: Sometimes, two miners find a valid block at roughly the same time. The network propagates both. The block that is eventually discarded (because another block builds on the alternative chain, making it the longest) is called an "orphan block" or "stale block." Its transactions are usually re-added to the mempool for inclusion in a future block.