An RDS file (R Data Serialization file) is a binary file format used by the R programming language to save a single R object to disk. Unlike the .RData or .Rda format, which typically saves multiple R objects from the global environment or a specified list, an RDS file is designed to store only one R object. This object can be anything from a data frame, a list, a vector, a statistical model, a function, or any other complex R data structure. The primary functions used for handling these files in R are saveRDS() to write an object to an RDS file and readRDS() to load it back into an R session. This format is highly valued for its ability to serialize and deserialize individual R objects efficiently, preserving their exact structure, attributes, and class information. This makes RDS files an excellent choice for sharing specific R objects between different R sessions, collaborating on projects, or persisting intermediate results without cluttering the global environment. They are generally robust across different R versions, ensuring compatibility when sharing data or code.