First, the bits and bytes
Bit: 0 and 1 is interpreted as a binary number system, and is referred to as bit ( 'bit, binary number).
Bytes: byte (byte) minimum computer memory cell. A byte has eight bits, 3 is the digital code 00000011.
Second, memory, and storage devices
Memory: the computer memory by one byte of the ordered sequence of, for storing programs and data required for the program (computer program is running and we need data are transferred from the memory storage device, a program and its data It must be moved before it is executed by the CPU memory ), as shown below. Each byte has a unique address, since it is possible to access bytes in any order, so the memory is also referred to as random access memory (Random-Access Memory, RAM) , what we called memory to run . Content bytes of memory is never empty, new information is placed in memory, the current contents of the byte will be overwritten lost.
Advantages: reading speed faster than the storage devices.
Disadvantage: RAM is a volatile form of data storage, such as when the power of information stored in the memory will be lost.
Storage: three types: disk drives, optical drives (CD and DVD) and USB flash drives.
Note: This article is an excerpt content from the Java Programming Language Basics chapter of
