These charms falling from the sky are realtime representation of bitcoin transactions as they happen.
These transactions are represented by different symbols and colours depending on the transacted amount, and other properties.
This is the blockchain. It shows the most recent 6 blocks, and the Genesis Block -- the very first block mined.
The blockchain is like a giant ledger. Every transaction since bitcoin's invention is recorded within. When a block is mined, transactions since the last block are included in the new block, which are confirmed by other miners in the network. Thus, transactions in the most recent block have one confirmation, and transactions from six blocks ago have six confirmations.