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What Is Bitcoin? Everything You Need to Know in 2026

Key Takeaways Bitcoin’s supply is limited to 21 million bitcoins. By comparison, fiat currencies like the USD grow in supply, decreasing their value. The Bitcoin blockchain serves as an immutable record of transactions. By contrast, traditional finance requires banks and financial institutions to track transactions accurately. Bitcoin’s value comes in part from its security. The Bitcoin network uses proof of work as both an incentive to keep the blockchain going and a disincentive for bad actors due to the cost involved with proof of work.

2026-07-17

What Is Bitcoin? Everything You Need to Know in 2026

What Is a 51% Attack? Meaning, Cost, and Examples

A 51% attack happens when a single person or group controls over half of a blockchain network’s computing power. With this level of control, they can block transactions, reverse them, and even double-spend coins. It represents a big threat to the security and trust of decentralized systems. While larger networks like Bitcoin and Ethereum are better protected due to widespread mining power, smaller blockchains with fewer participants face a greater risk. Key Takeaways Both Proof-of-Work (PoW) and Proof-of-Stake (PoS) blockchains can be vulnerable to 51% attacks, but the attack method differs for each system. Successful 51% attacks enable attackers to reverse transactions and double-spend coins, which can damage trust in the network. The cost of a 51% attack varies widely; it’s generally too expensive on large networks but feasible on smaller or newer blockchains. Preventing 51% attacks often involves enhancing network decentralization, security protocols, and community participation. Real-world examples like the Bitcoin Gold and Ethereum Classic attacks illustrate the potential consequences for crypto prices and security.

2026-07-14

What Is a 51% Attack? Meaning, Cost, and Examples

What Is a Blockchain Explorer, and How Do You Use It?

A blockchain explorer is a tool that gives you a window into a blockchain’s activity. From tracking transactions to viewing blocks, wallet addresses, and network metrics, blockchain explorers make blockchain networks transparent and accessible. These explorers let you see exactly what’s happening on the blockchain — down to the second a transaction is confirmed.

2026-07-06

What Is a Blockchain Explorer, and How Do You Use It?

Where Unconfirmed Bitcoin Transactions Are Stored

Unconfirmed Bitcoin transactions are usually stored in node mempools, not on the blockchain. They become on-chain only after miners include them in a block.

Can You Send Unconfirmed Bitcoins? What You Can Do

Yes, sometimes. Whether you can send unconfirmed bitcoins depends on wallet control, UTXO use, and features like fee bumping or spending change.

What Is Bitcoin Native SegWit?

Bitcoin Native SegWit usually means a bc1 address format that improves fee efficiency and modern wallet compatibility for everyday BTC transfers.

Why Is My Bitcoin Transaction Taking So Long?

A slow Bitcoin transaction usually means low fees, a busy mempool, or exchange-side delays. Check the tx ID, confirmation count, and wallet options first.

Why Your Bitcoin Transaction Stays Pending So Long

A Bitcoin transaction usually stays pending because the fee is too low, the network is busy, or the wallet never broadcast it properly.