Washington Square Park filled with purple gowns and black caps as about 6,000 students from New York University’s 14 undergraduate and graduate schools attended the university-wide commencement ceremony yesterday.

The university’s president, John Sexton, who called NYU “the world in microcosm,” and the student speakers stressed NYU’s wide role. “The NYU community transcends the boundaries that divide the world today,” a law school graduate, Rahim Moloo, said. A graduate of the School of Continuing and Professional Studies school, Marc Gustafson, who traveled the world for a nonprofit he founded before applying to college, asked graduates to think about a world less dependent on oil. “Our generation will have to face what the end of this era means and rise to the challenge,” he said.

The university presented several awards and honorary degrees. Rep. Charles Rangel, who graduated from NYU in 1957 and received an honorary degree in 1988, received the Lewis Rudin Award for Exemplary Public Service for his work in Congress and commitment to New York City.

The individual schools also hold their own ceremonies. During his address to the Medical School last night, Mayor Bloomberg called on graduates to become advocates for better public health, saying they should speak out on environmental injustice, gun violence, and poverty.

Today, Mr. Bloomberg will be in Houston to deliver a speech on energy policy and in Oklahoma, where he will tour the monument and museum dedicated to the 1995 Oklahoma City bombing and deliver the commencement address at the University of Oklahoma.