Welcome to a brief summary of Ark, this is meant to be short and to the point to give you an idea of what you are investing in. I alway recommend you read the Whitepaper for a more detailed explanation of the cryptocurrency you are interested in.
What is Ark? Ark is a blockchain that came into existence in March of 2017. It was created with the purpose of being an "all-in-one" blockchain solution. Ark acts as intermediary between blockchains, allowing a user to interact with multiple blockchains such Ethereum, Bitcoin, Litecoin. Ark calls this a Smartbridge. Smartbridge opens up great possibilities and flexibility, as now you can make transactions or enable smart contracts on other networks without having to actually download the blockchain's software or wallet. The applications are endless depending on what developers create in their ecosystem.
As far as technology running Ark, Ark is based on a Delegated-Proof-Of-Stake (DPoS) system. What this means is that the are 51 users who help secure the network and help the network run 24/7. These delegates are incentivized via transaction fees and Ark payouts. All Ark coin holders are allowed to vote for a delegate to represent them. Voters who voted for their delegate then get a payout from the delegate's earnings depending how much they contributed; the terms of payout vary by delegate. If a delegate is not fulfilling their duties or their system is down not helping secure the network, then a new delegate replaces them.
Ark is an inflationary coin, with no coin limit cap. Inflation will decrease over time, but here is a rough time table for the next 10 years. The first year will have an inflation rate of about 6.3%, 5.9% in the second year, and will continue to decrease to about 4% by the the 10th year.
Ark is an ambitious project and aims to be an ecosystem for multiple blockchains that can unite the cryptocurrency community. Learn more about Ark at https://ark.io/ .