Besides everything already said at the glossing of Portrait I would like to add the following about Dubliners:
Take a look at the Sparks note on the subject and also take a look at what Wikipedia has to say about it.
If it does not apeal to you or you are in a hurry, read this: (from Study.com)
Overview
James Joyce's Dubliners was published in 1914, and it was his first major work of fiction (he'd put out a book of poems a few years earlier). This collection of 15 short stories is important for several reasons. For one thing, it shows us how Joyce, who went on to write innovative and complex Modernist texts like Ulysses and Finnegans Wake, got his start writing simpler tales with more conventional prose. It's also notable as a portrait of middle- and working-class life in Ireland during a complicated period, when the country was struggling towards independence from England and its citizens were searching for a uniquely Irish identity.
Plot Summary
If you take a close look at the protagonists in each of these stories, you'll notice an interesting pattern: the first stories are all about children, and as the book progresses, it moves on to stories about young people and adults, finally ending with a middle-aged man looking back over his life in the last story, 'The Dead.' In a neat literary trick, the book progresses the way a human life progresses.
The Stories
The Sisters: A young boy and his aunt visit two sisters, who are keeping watch over the body of their brother, a priest.
An Encounter: Two boys skip class and gallivant around Dublin, till a meeting with a strangely lecherous old man frightens the narrator into retreat.
Araby: A bazaar called Araby provides the opportunity for a young boy to purchase a gift for his crush, the sister of a friend. However, he returns empty-handed.
Eveline: The title character has to make a decision: should she elope with her sweetheart to Argentina? At the critical moment, she abandons the plan.
After the Race: A young student tries to keep up with appearances, but foolishly spends all his money at the racetrack.
Two Gallants: Two down-on-their-luck drifters, Corley and Lenehan, plot to swindle a maid who works in a fancy house.
The Boarding House: Mrs. Mooney urges things along towards a marriage proposal when she sees sparks between her daughter, Polly, and one of her tenants.
A Little Cloud: Dinner with an old friend provokes Little Chandler to rethink his own life, including his failed ambitions as a writer and his sparkless marriage.
Counterparts: The frustrated alcoholic Farrington behaves violently in the pub, then goes home and beats his son.
Clay: The hardworking Maria goes to visit Joe and his family. She remembers how she used to take care of Joe when he was little.
A Painful Case: Mr. Duffy has feelings for Miss Sinico, but his prudishness causes him to end the affair. Four years later he learns that she has died and is filled with regret.
Ivy Day in the Commitment Room: Ivy Day celebrates the legacy of the famous Irish nationalist, Charles Parnell. In this story a group of political workers reflect on their work life and Parnell's memory.
A Mother: Mrs. Kearney is an overly ambitious mother who embarrasses herself and her daughter Kathleen during a concert.
Grace: A group of friends hope that religion can help straighten out the bumbling drinker Tom Kernan.
The Dead: Probably the most famous story in 'Dubliners', it follows Gabriel and his wife as they attend a party. Overcome by melancholy, Gabriel reminisces about his life and considers middle age.