You automatically (for free) get a copyright whenever you publish something to the world (book, article, blog, website, etc). Basically, a copyright means that no one else can copy (plagarize) you work. If they do, you may sue. But good luck proving damages or getting much money. You may also pay a small fee to get someone to check through your material and guarantee that it is your own work. However, paying this fee gives you no additional protection and may find that you cannot copyright parts (ie you stole parts).
A patent means you tell the world how to make your invention. In exchange, a government allows you to exclusively sell the invention for a period of about 17 years. If someone else tries to sell your patented invention in that country, you may sue and will likely win much if not all of the revenue generated (damages are easy to prove and money is easy to obtain). You must file a patent with each individual country that you want this protection. Patents start at about $20k for the US after attorney fees. Worldwide, you are looking at about $50k (plus the $20k for the US). Then you must pay yearly maintenance fees of a few thousand dollars.