Computer aided software engineering, also known as CASE, is a tool that helps people who make computer programs. Think about making a cake - it's much easier if you have all the tools and ingredients laid out in front of you, right? That's like using CASE to make a program!
CASE tools help people to write programs by providing them with the tools they need to create diagrams that show how the program works. Just like how you might draw pictures of your cake before you start baking, people who make programs can draw diagrams that show what the program will do before they start writing the actual code.
Using CASE tools can make the process of writing a program faster and easier, and it can help to minimize mistakes. That's because the tools can do things like automatically check the program for errors, or help people to write the code more efficiently.
In short, CASE helps people make programs faster, better, and more easily by providing them with tools to plan and create those programs.