Computer science is the study of algorithm
Modern computers are built using Von Neumann machine architecture.
Von Neumann machine have 3 aspects:
Computer memory is organized as a hierarchy. At the bottom, there is the hard drive. At the top level there is the CPU.
Because hard drives are slow, when a software is loaded, the software gets loaded in the Random Access Memory (RAM).
The RAM is still not fast enough for the CPU, so the instructions are actually executed in the Cache memory. HD: Probably TB in size RAM: Probably GB in size Cache: Probably KB in size
The memory is organized as an array or a table. Each row is 1 byte. 1 byte is 1 bit. 1 byte = 1 word
Address | 1 byte = 8 bits | |||||||
---|---|---|---|---|---|---|---|---|
0 (0000 0000) | 1 bit | 1 bit | 1 bit | 1 bit | 1 bit | 1 bit | 1 bit | 1 bit |
1 (0000 0001) | 1 bit | 1 bit | 1 bit | 1 bit | 1 bit | 1 bit | 1 bit | 1 bit |
2 (0000 0002) | 1 bit | 1 bit | 1 bit | 1 bit | 1 bit | 1 bit | 1 bit | 1 bit |
1111 1111 | … | … | … | … | … | … | … | … |