The Spanish Generation of '27 is the last generation of authors before the outbreak of the Spanish Civil War, which would wipe out almost totally the cultural and literary life of Spain for its duration and most of the following dictatorship. This generation is also considered the best poetry generation of the Spanish literature, with incredible figures like Federico García Lorca or Rafael Alberti, and it's studied as such in most of the schools in Spain.
The Generation of '14 were a group of writers, most of them poets, born during the change of century. The name comes from the homage they did for Luis de Góngora in the Ateneo in Seville in 1927 to celebrate the third centenary of his death, in which most of the authors that are part of the Generation of '27 took part.
The members of the group were very connected between them, but they each developed their own style and creative identity separately from the group. They were all famous writers in 1936, when the Spanish Civil War began, ending the most interesting political period of Spain and destroying Spain's cultural life. Some, like García Lorca, were killed; others like Miguel Hernández were put in jail; and most of them left on exile.
Many do not agree on calling them a generation because there's not exactly a common movement between them, but they do have similar characteristics. Most of them were born between 1892 and 1902 (except Miguel Hernández, born in 1901), and they all studied in the University (again, except Hernández). They've also got the same poet as a teacher: Juan Ramon Jimenez. But most decisive of all is that they all liked to work as a group and were friends between them, too.
The tendency towards balance is a very interesting aspect in the authors of the Spanish Generation of '27. For example:
In reality, the Generation of '27 wasn't a very homogeneous group, and they're normally grouped in twos or threes. For example, Rafael Alberti and Federico García Lorca, the Neo-folklorics, were closer to the poetry of Gil Vicente and the Romancero, looking for folkloric sources for their works. Jorge Guillén and Pedro Salinas were both professors of Spanish Philology, and tended to band together; their poetry is also similar in their optimistic view of life. In the surrealist group, the most important member is Vicente Aleixandre, of whom Cernuda, the other great Spanish surrealist poet, said that his verses "didn't resemble anything else". However, other components of this Generation of '14 did feel the impact of the Surrealist movement and went through periods of it, like Rafael Alberti, Federico Garcia Lorca or José María Hinojosa.
An exceptional feature about the Spanish Generation of '27 is that they didn't reject the previous movements and styles. Instead, they respected and admired them and the authors that developed them. Thanks to their synthesizing intention, the Generation of '27 is considered the richest and most admirable moment of all the Spanish poetry.