Why did Charles Babbage work on designing the early mechanical computer, such as the Difference Engine and Analytical Engine?

Introduction / Context:
Charles Babbage is often called the father of the computer because of his pioneering work on mechanical calculating machines like the Difference Engine and the Analytical Engine in the nineteenth century. Understanding his motivation helps you appreciate how the idea of computing first developed. This question asks why he began designing these early computers, focusing on the practical problem he was trying to solve.

Given Data / Assumptions:

- The question is about Charles Babbage and his early mechanical computer designs. - It mentions the Difference Engine and Analytical Engine as examples. - You must choose the main reason he worked on such machines.

Concept / Approach:
In Babbage's time, mathematical tables used for navigation, astronomy, engineering, and insurance were calculated by hand. These tables often contained errors because humans make mistakes when doing repetitive calculations. Babbage wanted a machine that could perform such calculations automatically and print accurate tables. His aim was to remove human error from the process, not to build a device for warfare, mass unemployment, or entertainment. Recognising this historical context leads you to the correct option.

Step-by-Step Solution:
Step 1: Recall that Babbage was a mathematician and inventor concerned with the accuracy of numerical tables. Step 2: Remember that he proposed the Difference Engine to compute polynomial functions and generate reliable tables automatically. Step 3: Understand that his Analytical Engine design went even further, introducing ideas like a central processing unit and memory. Step 4: Compare the options and see that option A directly matches his goal of automating calculations and reducing errors. Step 5: Eliminate options about secret messages, replacing all workers, or pure entertainment, as these do not describe his primary motivation.

Verification / Alternative check:
History of computing books, biographies of Charles Babbage, and museum notes about his machines explain that he was frustrated by the error filled printed tables of his time. He believed that a mechanical engine could calculate series accurately and print the results, leading to safer navigation and better scientific work. These sources repeatedly emphasise the goal of automation and accuracy in mathematical calculations.

Why Other Options Are Wrong:
- To create a device mainly for sending secret military messages: Cryptography was not Babbage's main goal when designing the Difference Engine or Analytical Engine, even though mechanical devices have been used for code work later in history. - To build a machine that could replace all factory workers in textile mills: This idea belongs more to the industrial revolution debate in general and not to Babbage's specific project. - To design a system for playing music automatically for entertainment only: While automatic music machines existed, Babbage's engines were not built with entertainment as their central purpose.

Common Pitfalls:
Students may confuse Babbage's work with later uses of computers, such as code breaking, automation, and entertainment. It is important to separate the original motivation of eliminating errors in mathematical tables from later applications. Keeping a clear mental link between Babbage and accurate calculation helps prevent such confusion.

Final Answer:
Charles Babbage worked on designing early mechanical computers mainly to automate complex mathematical calculations and reduce human errors in numerical tables.