1/10. For those familiar with blockchain tech, but don't understand Ethereum 2.0, I tried to simplify it into a tweetstorm. Some details are omitted, but hopefully it paints a decent overview.

2/10 ETH2.0 is secured by 'virtual miners' (validators) that collectively verify its integrity. To become a validator, you have to stake 32 ETH. You now form part of an active set of validators: ready to work. If you have more ETH, you can create more validators.

3/10 The beacon chain is the core orchestrator for consensus: tasking the validators in doing honest work. A maximum of 64 shards execute the computation (much more capacity than ETH1.0).

4/10 All this work is divided into epochs. Each epoch contains 32 slots. Each slot is 12 seconds. An epoch is thus 6.4 min.

5/10 In an epoch, each validator will be asked to vote on the beacon chain itself, a checkpoint for finality, and will also be assigned a random shard to crosslink (anchor). 32 validators will be assigned the additional role of a block proposer for each slot.

6/10 A validator will be expected to cast their vote on a proposer's block in a randomly assigned slot. In order to ensure integrity, each validator will form a part of a committee: tasked to do the same work.

7/10 The minimum size of a committee is 128 validators. A validator will only be a part of one committee per epoch. More than one committee can be assigned to a slot. The difference for each committee is 1) in what slot it is, and 2) what shard to crosslink.

8/10 If you are an honest validator, and you miss your work, you lose what your reward would've been. Thus: If you cooperate honestly > 50% of the time, you will earn a profit. < 16 ETH, you are kicked out.

9/10 If you clearly cheat, or act against consensus, however, other validators can point it out and you will be slashed, losing much more ETH. An example: a block proposer proposing more than one block per slot.

10/10 This will be released in phases: phase 0 -> beacon chain, phase 1 -> shards, phase 1.5 -> bring in ETH1.0, phase 2 -> execution engines for shards.

11/10 There's a lot more finer details if you are interested in diving in. Thanks to @benjaminion_xyz for fact checking.

If there's something I still missed, let me know.

Sources:
https://ethos.dev/beacon-chain/ 
https://medium.com/coinmonks/ethereum-2-0-beacon-chain-explained-70287fc9901b https://www.reddit.com/r/ethereum/comments/eay6lz/supersimplified_explanation_of_the_beacon_chain/