Protecting a website idea

You can not protect it. Your only option is to out-compete. People will copy your good ideas every step of the way.

What @Genadinik said is ultimately true. You need to get the edge by being first, and keep it through hard work, your ideas if successful will be copied.

You can, and should, establish a trademark, but that will only do so much for you. Someone can start another company under another name and still steal the idea.

One point that I wanted to add with my answer is that you can copyright your content, making the idea harder to steal. If you can build a community of people generating content for you, and make sure that you have copyright on that content, then competitors would not just need to steal your idea but also your community.

So hitting the ground first gets you users first which gives you the best chance to keep the snowball building. Copyrighting content will give you the most powerful defense. In the end though no protection is perfect, you just have to stay competitive.

The bottom line is that you can't. Just because another company has more money doesn't mean they can or will make a better product than you. Prime example is Apple, once upon a time not so long ago Microsoft was worth more than Apple. Both software companies, both in a way in direct competition and look at Apple now?

It's the execution that matters. You'll read this everywhere you look for advice, focus on the execution because copying execution is a lot harder than merely copying an idea which is easy.

To add to what everyone else has said, few people will want to copy exactly what you do. Sure they'll want to copy your success and they'll borrow some elements, but they'll change parts of it because that's just what they do. How many times have you seen a small company do something really "cool" and get popular, and then when a larger company copies it everyone thinks it's "fake" and they fail?

This isn't always the case - sometimes it's really obvious what makes you successful and easy to copy, and sometimes they may improve it - but if your potential competitors just think you're crazy that gives you some protection :)

Most companies aren't in actual direct competition. Instead each company decides to go after a different type of customer, which often drives away other types of customers (to a "competitor").

Ultimately what @Genadinik is the bottom line. I truly believe you need to build your software fully expecting that someone else is working on the exact same idea. Expect competition, differentiate yourself when it comes & win.