Javascript error : Uncaught Reference Error

https://spiromarshes.com/ . This is my website
The website have some javascript errors . For some reason the console show " Uncaught ReferenceError: c is not defined " . Can someone explain what does it mean and give me some tips to solve this problem .

Hello!

The error seems to be coming from your scripts.js. What are these scripts for, and where are they from?

Edit:
More specifically, this function is causing the error

// Function to ping servers
$(function(){
	
		$('.pingUp').attr('data-count',c)
		.countTo({
		    from: 0,
		    to: c
		});
});

What servers are you pinging, and what for?

I am trying to show how many users are online in this site https://survivewith.us/ . When you click the logo in the middle it opens a pop up box and at the bottom of the pop up box i want to show how many are online. Right now it shows loading status but not how many are online .

http://next978.000webhostapp.com/ .
The particle js loads first time in chrome , but when i reload it again it no longer works . Can someone explain the reason behind it and give me suggestions on how to fix the issue