So far, we have learned how to write programs and communicate our intentions to the Central Processing Unit using conditional execution, functions, and iterations. We have learned how to create and use data structures in the Main Memory. The CPU and memory are where our software works and runs. It is where all of the “thinking” happens.
Checkpoint8.1.1.
Q-1: Where does the software work/run on a device? Select all that apply.
Central Processing Unit
The CPU runs the software in conjunction will memory sources.
Input Devices
Input devices supplement the software and other hardware.
Memory
Memory sources run the software in conjunction will the CPU.
Network
The network does not run software.
But if you recall from our hardware architecture discussions, once the power is turned off, anything stored in either the CPU or main memory is erased. So up to now, our programs have just been transient fun exercises to learn Python.
Figure8.1.2.
In this chapter, we start to work with Secondary Memory (or files). Secondary memory is not erased when the power is turned off. Or in the case of a USB flash drive, the data we write from our programs can be removed from the system and transported to another system.
We will primarily focus on reading and writing text files such as those we create in a text editor. Later we will see how to work with database files which are binary files, specifically designed to be read and written through database software.
Checkpoint8.1.3.
Q-2: Which piece of hardware are we working with in this chapter?
Main Memory
What type of hardware are files?
Secondary Memory
This chapter focuses on files which is a part of secondary memory.
