Dividing your disks into partitions allows you to use each partition for separate tasks.
Would you buy a house that had a single cupboard in the kitchen with one giant shelf? No drawers to keep forks and spoons. Just one big storage space. What if you had to keep your clothes there too?
And while at work or school, would you use a single roll of paper instead of separate sheets that can be stored in folders?
We need to organize things and that goes beyond just sorting. We need to group things too. These groups can be used for very different things. As computer disks have grown in capacity over the years, the need to divide them into multiple groups has grown.
This is called partitioning your disk. Each partition can then be used for different purposes. Maybe you want one partition to hold all the operating system files. Another partition can hold your applications. Another for data file you create. Another for log files that record useful information about what your computer is doing. Another for swap space that the operating system can use when the main memory gets low. The reasons are as plentiful as there are people to use computers.
Listen to the full episode for more details including a description of the Master Boot Record (MBR) and GUID Partition Table (GPT) partitioning schemes.