Week 08 – Computer software & Python programming

Table of Contents

Lesson Overview

Topic: Computer Software

Activities & Due Dates: [Activity 5] Python Programming

Students will be able to

•Install ntpdate application

•Restart the software

Computer Instructions or data, anything that can be stored electronically is Software.
Hardware is one that is tangible. The storage devices (Hard disk, CD’s etc.,), mouse, keyboard CPU and display devices (Monitor) are Hardware.
For example: There is a problem in the Software implies – Problem with program or data
Computer Software
- Computer hardware is useless without software.
- Software is the set of instructions and associated data that direct the computer to do a task.
- Software can be divided into two categories:
  - System software: helps the computer to carry out its basic operating tasks.
    - Operating Systems, device drivers
  - Application software helps the user carry out a variety of tasks.
    - Microsoft Office, Games

Operating System is a software, which makes a computer to actually work.
It is the software the enables all the programs we use.
The OS organizes and controls the hardware.
OS acts as an interface between the application programs and the machine hardware.
Examples: Windows, Linux, Unix and Mac OS, etc.,

•Cmd on search bar or find Command Prompt in Windows Systems Menu

Run a target process. E.g. notepad.exe

Find the process. Using tasklist

Kill the process through command

Hardware doesn’t know where the operating system resides and how to load it.
Need a special program to do this job – Bootstrap loader.
- E.g. BIOS – Boot Input Output System.
Bootstrap loader locates the kernel, loads it into main memory and starts its execution.
In some systems, a simple bootstrap loader fetches a more complex boot program from disk, which in turn loads the kernel.
BIOS
- Basic Input/Output System
- Contains information about the machine’s configuration.
- Eg. IDE controller, NIC
- PC knows which device to boot from via BIOS
- PC tries to run code from the MBR, ie. 1^st 512 bytes, of the disk
- MBR tells the PC to load the boot loader from certain disk partition
- The boot loader loads the kernel

On finding a bootable device, the BIOS loads and executes its boot sector. In the case of a hard drive, this is referred to as the master boot record (MBR).
The MBR loads a boot sector in the hard drive and executes it.
The boot sector is often operating system specific, however in most operating systems its main function is to load and execute a kernel, which continues startup.
Then execute the processes written in the boot scripts