What is the different between investment and speculative?

Many people around us are thinking they are doing investment instead of speculative. So what is the different between investment and speculative?

According to Benjamin Graham from The Intelligent Investor,

An investment operation is one which, upon through analysis promises safety of principal and an adequate return. Operations not meeting these requirement are speculative.

So do your investment give you any safety promise? and adequate return?

I believe the safety that Graham mentioned is mean by no losing your capital and the investment you do always give you a safety of margin by buying a investment equity by a "bargain" or "discount" and the adequate return is mean by give you a reasonable return, not too high not too low.