Essentially, the Renaissance was an efflorescence of arts, primarily visual but also to a lesser extent literary, and ideas in Europe that coincided with the rediscovery of Roman and Greek culture. It's easiest to see this in terms of visual art. Renaissance art tends to feature a focus on the human form, somewhat idealized, as Roman and especially Greek art had. And this classicizing is also rather apparent in the architecture of the Renaissance, which featured all sorts of Greek columns and triangular pediments and Roman arches and domes. In fact, looking at a Renaissance building, you might even be able to fool yourself into thinking you're looking at an actual Greek building if you sort of squint and ignore the fact that Greek buildings tend to be, you know, ruins. In addition to rediscovering, that is copying, Greek and Roman art, the Renaissance saw the rediscovery of Greek and Roman writings and their ideas. And that opened up a whole new world for scholars.