A value proposition is a promise of value to be delivered. It's the primary reason a prospect should buy from you.
Your company website should have a value proposition, as should each product or service you're selling.
Your value proposition is the #1 thing that determines whether people will bother reading more about your product or hit the back button. It's also the main thing you need to test - if you get it right, it will be a huge boost because your potential clients will "get" exactly what you're about. If I could give you only one piece of conversion advice , "test your value proposition" would be it.
In a nutshell, value proposition is a clear statement that:
You have to present your value proposition as the first thing the visitors see on your home page, but should be visible in all major entry points of the site.
Remember, your value proposition is something real humans are supposed to understand. It's for people to read. Here's an example of what a value proposition is NOT supposed to be like:
Revenue-focused marketing automation & sales effectiveness solutions unleash collaboration throughout the revenue cycle
Would you be able to explain to your friend what the offer is and how they'd benefit? Didn't think so. Unfortunately it's no joke. Such meaningless jargon-propositions are abundant.
Here are some screenshots of really great value propositions: