Cardano is a 3rd generation blockchain platform which is more scalable and energy efficient by design compared to previous generations of blockchain like Bitcoin and Ethereum. The native currency of the Cardano ecosystem is called ADA, named after Ada Lovelace, the 19th-century mathematician often referred to as the “world’s first computer programmer”, and is the daughter of the poet Lord Byron. Cardano uses a Proof of Stake protocol called Ouroboros for the consensus mechanism of its network. With support for smart contracts, Cardano aims to host an ecosystem of decentralized applications to manage identity, value and governance. Cardano has been built from the group up based on peer-reviewed scientific research. This approach to development of Cardano is one of its hallmarks, making it a sound ecosystem that can act as a decentralized financial operating system for the world.
Cardano was ideated in 2015 and launched in 2017. The development of Cardano is envisioned as through these five phases
Proof of Stake:
Proof of stake (PoS) is a type of consensus mechanism or protocol that uses the amount of stake (or value) held in the system to determine consensus. The consensus protocol controls the laws and parameters governing the behavior of blockchains. In a decentralized environment the consensus mechanism enables the blockchain to sustain as a single source of truth about the transactions that occur.
Stake pool
Stake pools are responsible for processing transactions on the Cardano blockchain. Ouroboros protocol relies on stake pools, to create blocks which are aggregates of several transactions. ADA holders can bring their ADA to form a pool and become a stake pool operator. Alternatively ADA holders can participate in the network operation passively by delegating their ADA to an existing stake pool.
Delegation
Through delegation ADA holders can support a stake pool to generate blocks for the Cardano network. The rewards for block creation will be distributed to the delegators in proportion to their staked amount after the fees for the SPO.
Commonly used tools for exploring the transactions and block details are https://explorer.cardano.org/en.html and https://cardanoscan.io/. You will find other tools out there as well as is usual in the Cardano community.