Some criminal defendants opt for a jury to try to prove that they aren't guilty of a trial. This process is a lengthy one, but the end result is that a group of that person's peers listens to the facts of the case as they are presented by the prosecution and the defense during the trial.
The right to a jury trial is one that is provided in the United States Constitution, but it doesn't apply to every criminal case. Instead, the Sixth Amendment provides the right to a trial before a jury of your peers if you are facing at least six months in prison or jail if you are convicted. This means that some misdemeanors might not be eligible for this type of trial.
When you have this type of trial, you aren't going to see a jury that represents you. The courts have noted that the jury should be a cross section of the community and not a jury of people who are similar to you. During the process of selecting these individuals, the judge, the prosecutor and the defense attorney can all question potential jurors to determine if they are a good fit for the case. It is possible to call the suitability of some people into question and possibly reject them.
For example, a police officer's spouse isn't a good fit for a case involving a claim that the defendant attacked a police officer. In this case, that spouse might be bypassed since it is assumed that they can't give the case impartial attention.
Once the trial is over and both sides have presented their cases, the jury will deliberate their decision. Ultimately, they need to have a decision on each charge they hear as part of the matter. This will be either guilty or not guilty. The goal of your defense is to have them find that there is reasonable doubt about whether you committed the crime or not. This would be a not-guilty verdict.