Ethereum

Purpose:
Bitcoin: Primarily designed as a digital currency and a store of value. Its main function is to facilitate peer-to-peer transactions without the need for intermediaries.
Technology:
Bitcoin: Utilizes a simple scripting language for transactions, which limits its programmability. It is primarily a ledger for tracking ownership of bitcoins.
Consensus Mechanism:
Bitcoin: Uses a Proof-of-Work (PoW) consensus mechanism, which requires significant computational power and energy consumption to validate transactions and secure the network.
Supply:
Bitcoin: Has a capped supply of 21 million coins, which creates scarcity and is designed to be deflationary.
Transaction Speed and Fees:
Bitcoin: Generally has slower transaction speeds and higher fees during peak usage times due to its block size and time constraints.
Community and Development:
Bitcoin: Has a more conservative development approach, focusing on security and stability.