windows - Committed Bytes and Commit Limit - Memory Statistics

I'm trying to understand the actual difference between committed bytes and commit limit. From the definitions below,

Commit Limit is the amount of virtual memory that can be committed
without having to extend the paging file(s). It is measured in bytes.
Committed memory is the physical memory which has space reserved on the disk paging files.

Committed Bytes is the amount of committed virtual memory, in bytes.

From my computer configurations, i see that my Physical Memory is 1991 MB, Virtual Memory (total paging file for all files) is 1991 MB and Minimum Allowed is 16 MB, Recommended is 2986 MB and Currently Allocated is 1991 MB.

But when i open my perfmon and monitor Committed Bytes and Commit Limit, the numbers differ a lot. So what exactly are these Committed Bytes and Commit Limit and how do they form.

Right now in my perfmon, Committed Bytes is running at 3041 MB (Sometimes it goes to 4000 MB as well), Commit Limit is 4177 MB. So how are they calculated. Kindly explain. I've read a lot of documents but I wasn't understanding how this works.

Please help. Thanks.