One thing we can learn from the opening scene in Shakespeare's Romeo and Juliet concerns the depth of the feud between the Capulets and Montagues and just how much it is involving and affecting the entire city of Verona.
We learn that the feud not only involves the family members of Lords Capulet and Montague, it has also come to involve their entire households, as we see through the conversation between Capulet's servants, Sampson and Greggory. We see Greggory point out that because their master, Lord Capulet, is fighting with Lord Montague, their households, including their servants, believe they should be fighting as well, as we see in his line, "The quarrel is between our masters and us their men," showing us just how many citizens the family feud is affecting (I.i.17).
We further learn just how much the feud is affecting the entire city of Verona through the Prince's speech. Prince Escalus points out that three times now has the fight between Lords Capulet and Montague turned into a whole-city riot and for each of these three times, the riot has been started by something trivial either Capulet or Montague said to each other, as we see in Prince Escalus's lines:
Three civil brawls, bred of an airy word
By thee, old Capulet, and Montague,
Have thrice disturb'd the quiet of our streets. (85-87)
The term "airy" can be translated as "meaningless," or trivial, showing us that the fights start due to trivial comments and then progress into whole-city riots. Hence, we see through this passage that the feud is not only affecting the Capulet and Montague households, it is involving the entire city. Thus we see just how deeply entwined with the citizens the feud has become.
The first scene of Romeo and Juliet is important because it establishes the feud beteween the Capulets and the Montagues, the two primary families in the play. It also introduces us to the characters of Romeo, Benvolio and Tybalt.
The scene opens with two Capulet servants, Sampson and Gregory, discussing what they would do if a Montague came along. Sampson prides himself on his courage, saying he would attack if provoked or insulted. Gregory jokingly calls his fellow servant a coward. When a servant of the Montague household comes along, words are exchanged and a fight insues. Benvolio, of Montague house, tries to stop the fight, but is interrupted by Tybalt, who picks a fight with him. The fight spreads until the entire street is filled with members of the Capulet and Montague households fighting. Both Lord Montague and Lord Capulet attempt to enter the fight, but are stopped by their wives. The Prince of Verona finally arrives and pronounces a sentence of death for anyone of either house who disturbs the peace in the city again.
After the fight is over, the Montagues question Benvolio about the fight and then mention to them that their son Romeo has been acting strange lately. BEnvolio promises to find out why and speaks to Romeo, who tells him that he is depressed because he loves a girl who will not respond to his advances. Benvolio suggests that Romeo look at other girls so that he will forget this one.
This scene gives us valuable insights into the characters of Romeo, Tybalt and Benvolio. Romeo is established as a melancholy, emotional person who stubbornly sticks to his feellings, even if those feelings are inappropriate. Tybalt is established as a hothead, as he refuses to listen to reason and continues a fight that Benvolio was attempting to stop. And Benvolio is established as a calm voice of reason and a true friend to Romeo.