Pride and Prejudice is often described as a novel of 'manners'. Put simply, it's about how people interact, and how the feelings you show in public can often be very different to your true feelings.
Jane Austen originally called the novel 'First Impressions'. This is because the two main characters, Elizabeth Bennet and Fitzwilliam Darcy, form very strong opinions of each other based on their first impressions, and these affect the way they act.
The Bennet family (Mr and Mrs Bennet and their five daughters: Jane, Elizabeth, Mary, Kitty and Lydia) live in Longbourn, Hertfordshire. They discuss the expected arrival of Charles Bingley, a rich young man who'll soon be living at a nearby estate called Netherfield. Mrs Bennet wants her husband to go to meet him, as he might make a good husband for one of her daughters. Marrying them off is her main concern in life.
Mr Bennet visits Bingley, but doesn't let his wife know and teases her about it. She becomes annoyed, before being pleased when he reveals he's spoken to him.
Bingley brings some friends from London to attend a ball at his house. Fitzwilliam Darcy is a close friend and impressive figure, especially as he's even wealthier than Bingley. Darcy will only dance with Bingley's sisters (Mrs Hurst and Miss Bingley).
Bingley, who's been dancing with Jane Bennet, tries to get Darcy to dance with others, and points out Elizabeth. Darcy coldly and arrogantly rejects the idea, saying Elizabeth isn't good looking enough for him. She overhears this but laughs it off with her friends.
Elizabeth and Jane talk about the ball and the Bingleys. Jane likes everyone, but Elizabeth is suspicious of the Bingley sisters. Bingley likes his new neighbours - Darcy doesn't.
We meet the Lucas family. Elizabeth is close friends with the daughter, Charlotte. Mrs Bennet is still very happy about Bingley liking Jane, though still angry about Mr Darcy's rudeness.
The Bingley sisters are nice to Jane, but not genuine. Jane meanwhile doesn't want to show her true feelings for their brother. Charlotte thinks it will help if she does, but Elizabeth explains that she isn't like that.
The Lucases have a party and Sir William Lucas tries to get Darcy to dance with Elizabeth. Darcy is put on the spot and agrees, but Elizabeth coldly refuses. This surprises Darcy - and he becomes attracted to her.