Linux divides it physical RAM (random access memory) into chucks of memory called pages. Swapping is the process whereby a page of memory was copied to the preconfigured space on the hard disk, called swap space, To free up the that page of memory. The combined sizes of the physical memory and the swap space is the amount of virtual memory available.
Linux divides physical memory into chunks of memory called paging (page). Memory swapping is the process by which a memory paging is copied to a preconfigured hard disk space called swap space to free up memory paging. The common size of physical memory with this swap space is known as the amount of virtual storage available.
Here, there are two important reasons to keep the swap partition.
One is that when physical memory is not sufficient to support the operation of systems and applications (processes), the swap space can be used as a temporary memory paging for low usage, freeing up memory to be used by much-needed applications (processes).
Again, even if your machine has enough physical memory, there are programs that will let out the physical memory space by transferring to the swap space the very few memory paging content that remains when they are initialized. Swap space is more important for applications (processes) that have a memory leak chance, because no one wants to see the system crash due to insufficient physical memory.
Simply put, memory is not too much. Swap is used when it's not enough, swap to swap if you don't use it.
Linux Swap partition function