I have a set of articles in salesforce. But in order to reduce the navigation from our website to another, we are planning to embed these articles on the website itself. I want to know if there is a way to embed the salesforce app as an iframe on another third party website.
The developer docs provides ways to embed the third-party websites to salesforce but is there some documentation for doing the opposite?
It doesn't have to involve any code so try these out and maybe next time ask on https://salesforce.stackexchange.com/
If you plan to use normal SF authentication search around about Lightning Out. It's a way to expose Aura components in non-Aura environments (Visualforce but also totally standalone pages written in other languages. You could even make an Outlook plugin if you want). It even has something to work with guest users (without SF login), haven't used it but looks like you'd have to prepare something extra to make it work.
Or
You could create a Community in Salesforce (customer community, partner community, doesn't matter much. What will matter is what access you'll give to "guest user", will you let them read all articles. Guest users could browse your product catalog, fill in some contact us form, read articles... without logging in. Up to you how much you want to do on your website vs Salesforce platform ;) There's also similar option without Community but with bit of coding - read up about Visualforce Sites.
Sites are free (some monthly traffic limits apply). Communities - actually I'm not sure. You might be able to have Community for free if you don't plan to buy any user licenses for it. Check with your account manager.
You can go quite far styling them. Can you tell these are built on Salesforce?