Subnetwork
The host portion of an IP address of all zeros indicates that you are referring to 'this network'. For example, the address 145.5.0.0 means the network 145.5
Digital quantities are represented by binary numbers (ONES and ZEROS). The binary ONES and ZEROS make up a word or number that indicate a value. Each bit position represents a portion of the overall quantity.
When you set up a sub network you decide upon the subnet mask and this determines the network address (all zeros in the subnet portion of the address) and the broadcast address (all ones in the subnet portion of the address). When you assign the host addresses in your subnet, then you use the addresses between the network address and the broadcast address.
You may be thinking of the binary number system.
Binary code, zeros and ones.
No, binary numbers don't consist of ones and twos, they are ones and zeros.
Binary
binary
It is called binary.
Binary Data
Not quite sure what you mean by "holes"; "binary data" consists of a string of ones and zeros.
A megabyte (MB) is commonly defined as 1,024 kilobytes in the binary system, which translates to 1,048,576 bytes. In the decimal system, 1 megabyte is defined as 1,000,000 bytes. Therefore, in terms of zeros, a megabyte in the decimal sense has six zeros (1,000,000), while in the binary sense it can be represented as 1,048,576, which has no trailing zeros.