Dimensions: Starting from 0, the real number axis symmetrically extends infinitely in both directions. Traditional business is one-dimensional: each business operates with fixed manual labor costs. Internet business is two-dimensional: merchants and buyers are distributed in a many-to-many matrix-like structure on platforms, like Taobao. $ETH is three-dimensional: it adds a platform maintained by a limited number of PoS staking nodes. However, tokens on the EVM still remain in two dimensions, essentially no different from cloud platform businesses. $BTC is four-dimensional: beyond extending the third dimension of nodes from $ETH to infinity, it also adds a time dimension. The time dimension is irreversibly generated, and its creation involves the addition of two dual dimensions. One dimension is the infinite non-cooperative game of nonce collision competition, while the dual dimension is the infinite possibilities of a Turing ordinal logical system structure. Therefore, $BTC is essentially a 5-dimensional design structure forming a 4-dimensional system structure.