Patricians: The patricians were the upper class, the nobility and wealthy land owners. 

Plebeians: The plebeians were the lower class. Nicknamed "plebs", the plebeians included everyone in ancient Rome (except for the nobility, the patricians) from well-to-do tradesmen all the way down to the very poor. 

Things that were the same in both classes  

Pater Familias: The family was structured in the same way in both classes. The head of the family was the oldest male. That could be the father, the grandfather, or perhaps even an uncle. Everybody in one family lived under one roof. Women had no authority except in the home. Old age was honored.  

Atrium: Life in the home of wealthy tradesmen and patricians centered around the atrium, the central courtyard. 

Slaves: If they could afford it, both classes had slaves to do the work.

Citizenship: The citizens of Rome were adult freemen from both classes - plebs and patricians. Women, children, and slaves were not citizens. People from all classes considered themselves Romans. 

Religion: Both classes worshiped the same gods and attended religious festivals. 

Language: Both classes spoke the same language, Latin.

Forum: Both classes enjoyed the activities in the Forum, including the many free activities such as jugglers. 

Things that were different  

Social Life: A wealthy plebeian family and a wealthy patrician family did not meet socially. Under the kings, it was illegal for a pleb and a patrician to marry. In 445 BCE, about 60 years after the Roman Republic was formed, a new law was written that said it was no longer illegal for plebs and patricians to marry.

Apartment Houses: Many plebeians lived in apartment houses called flats. Some the apartments were above or behind their shops. Even fairly well to do tradesmen might chose to live in an apartment-building compound over their store, with perhaps renters on the upper stories. Their own apartments might be quite roomy, sanitary and pleasant, occasionally with running water. But others were not that nice.

The Poor, Unsanitary Living Conditions: In the poorer apartment houses, an entire plebeian family (grandparents, parents, children) might all be crowded into one room, without running water. They had to haul their water in from public facilities. Fire was a very real threat because people were cooking meals in crowded quarters, and many of the flats were made of wood. They did not have toilets. They had to use public latrines (toilets).  The lower class Romans (plebeians) might have a breakfast of bread, dry or dipped in wine, and water. Sometimes olives, cheese, or raisins were sprinkled on the bread.

Rich and Poor Life Style: The rich had beautiful mosaics on the floors of their home. They wore lots of jewelry made of gold and gemstones. They had beautiful clothing. They enjoyed a great deal of leisure time. The poor wore shabby clothing. Their jewelry was made of painted clay. They worked all the time. 

Patricians and Plebeians

Plebs - Why were they called plebs?