Much like mediation, arbitration is another way to resolve disputes before going to court. Arbitration, however, is a much more formal and quite more expensive way to resolve disputes. Arbitrator's fees can be very high (sometimes even $1,000 per hour). Although the parties can voluntarily agree to arbitrate a claim, this is usually not the case. Most times we find ourselves caught in arbitration because we agreed to it a long time before. For example, when you get a credit card, the fine print terms and conditions will often say that, if you ever have a dispute with your credit card company, you agree to arbitrate rather than sue each other.
An arbitral resolution is binding on the parties even without their signature. Getting out of an arbitral resolution is a very difficult process. This is why it's fundamental that you protect your rights with the held of an attorney during arbitration, rather than after.