Arraignment
  
If you are at an arraignment and you aren’t getting paid to be there, you’re probably having a really bad day.
An arraignment is a court proceeding that takes place early in the criminal justice process. A judge, or maybe a clerk, reads out the charges. Then the person accused of the crime enters a plea. There's some nuance to all this, but generally the accused says whether they are guilty or not guilty. Depending on their plea, the proceedings will move to the next phase, either determining a sentence (if they admit guilt) or moving on to trial (if they claim innocence). These further steps generally take place at a later date.
Again, the precise course of events depend on the jurisdiction and the rules of the particular courts. The main goal is to make sure that the accused person understands the charges and give them an opportunity to state their guilt or innocence.