Summary:

• IOTA is a ground breaking new open-source distributed ledger that does not use a blockchain. Its innovative new quantum-proof protocol, known as the Tangle, gives rise to unique new features like zero fees, infinite scalability, fast transactions, secure data transfer and many others.
• IOTA is initially focused on serving as the backbone of the Internet-of-Things (IoT).
• IOTA’s goal is to become the de facto platform for executing transactions between IoT devices. Given how estimates suggest there could be 20.4 billion such devices out there by 2024, this could end up being big business.

Overview:

IOTA aims to be the backbone for the financial system of the IoT. Additionally, it also has integrated other features like secure messaging and a data marketplace. These features are all part of the future machine economy envisioned by IOTA in which millions of machines exchange data and payments in real time.

Because there’s no blockchain, there are no miners, and because there are no miners, there are no fees. Many established networks see costs balloon when congestion intensifies, but IOTA aims to provide limitless throughput at minimal expense.

Technology:

IOTA's is a distributed ledger, the Tangle, is based on a data structure referred to as a Directed Acyclic Graph (DAG) rather than a blockchain. In the Tangle there are no blocks or miners, and every transaction on the Iota network must validate two previous transactions through a small proof-of-work (PoW). Therefore, users who issue a transactions are contributing to the network's security. Transaction on IOTA are stored in the tangle graph, which is the ledger for storing transactions.

IOTA network currently relies on a coordinator node that provides trusted milestone transactions, and snapshots which are used to reduce the size of the network. The coordinator node is a special node that is operated by the IOTA foundation designed to protect the IOTA network from attacks while it grows.  The IOTA development roadmap mentions several programming languages: Rust, Go, Javascript, Java and C++. IOTA plans to remove the coordinator once the network reaches scale. Furthermore, it eventually plans to incentivize full nodes to store the entire Tangle history beyond snapshots issued by the IOTA foundation.

Use of Native tokens in the ecosystem:  IOTA is used for facilitating transactions, and used to process micropayments.