Why Human need to wear cloths!?

Today Morning. I had a question myself that Why we need to wear cloths, Why we cover private parts? What are the private parts? What does it means by private? and what is so special about it?

I am searching for a root cause and exploring related topics like when did human start wearing cloths and why?? I will let you all know if i found something..

Things to note:

• No other animal beside human wear cloths.
• Human wears Clothing since last 100,000 years.
• Clothings are already psycologically attached to human as we afraid to live without them.

You additional opinions on the Topic as comments is welcome !!!