How do I count downloads from my website

Create a javascript function on the onclick event of the link that allow the user to download the file and at the same time, update the counter on the second file. we are new to this concept.plz help us

We have two files in server .We download file like this

<a href="192.168.3.134:8080/Helphands/download.txt"; download> aaaa </a> in button action .

We don't know about update count on second file