Duplicate: This is a duplicate of "What are the best uses of REST services?" and many others. Please close it.
In web development:
Should i learn RESTful services very well and make all my future projects using it? Is it faster than SOAP services? When to use which?
There is certain cases i should use one of them and others no?
In my experience, SOAP adds some overhead that you can avoid by making a RESTful service. That being said, in your decision, you should consider your audience. If you are expecting to have a large variety of outside-world consumers of your service, I would recommend SOAP, because there are a lot of tools that automatically generate a programmatic interface to it.
Some web services, like PayPal, offer multiple alternatives, so you could also consider choosing both.
REST should be faster than SOAP in most cases since it is more light weight, less overhead.
But there are some situations in which you need the functionality that is in that overhead.
Unless you want to standardise on one (this reduces the number of technologies in your solution, and therefore the complexity), the rule of thumb would be use REST when you can and SOAP where you must.
Absent a clear requirement to the contrary, you should always prefer REST to SOAP. There are (rare) times when SOAP provides you with what you need (and those times will get more rare as REST improves, such as having a WADL standard), but in the general case, SOAP is just a whole lot of headache to get you where REST is already standing and waiting.
To directly answer your question, I'd say yes. REST is usually regarded as the lighter alternative. Also, at the current stage, REST is still consider/practiced by many to be more of a "direction/guideline" then a full protocol.
There's an interesting article depicting their differences in an interesting dialogue.
Personally, I'd say REST should be pretty much better than SOAP in all cases a normal person would choose. On the other hand, designing a true REST architecture requires a lot of planning and considerations. Most attempts fail at that and become STREST (mentioned in the above article), which is like mixing SOAP and REST and losing some of the benefits REST provides.
One factor is that RPC communications are often not cached as part of the HTTP stack because the caching middleware shouldn't need to understand the contents of the request. So, RESTful systems can take better advantage of caching.
REST will almost always be faster since there's less processing and smaller envelopes.