Structured Systems Analysis and Design Method (SSADM) is a way to plan, analyze, and design computer software. It helps people create systems that are easy to use and understand. To do this, SSADM breaks the project down into small steps and explains what each step does. After that, people can start creating the system and make sure it will do exactly what they want it to do.
SSADM is like a recipe for making software. First, you figure out what you want the software to do - this is called the requirements. Then, you write down what each step of the process should be - this is called the design. Once the design is ready, you start making the software. When it's done, you use it to do the task you wanted it to do.
SSADM makes it easier to create systems that work the way they should and are easy to use. This is why it's so popular in the software industry!