RDF compression can be defined as the problem of encoding an RDF dataset using less bits than that required by text-based traditional serialization formats like RDF/XML, NTriples, or Turtle, among others. These savings immediately lead to more efficient storage (i.e., archival) and less transmission costs (i.e., less bits over the wire).
Although this problem can be easily solved through universal compression (e.g., gzip or bzip2), optimized RDF-specific compressors take advantage of the particular features of RDF datasets (such as semantic redundancies) in order to save more bits or to provide retrieval operations on the compressed information. RDF self-indexes are focused on this latter task.
J. Fernández, A. Hernández-Illera, C. Gutiérrez, M.A. Martínez-Prieto, RDF Compression, In: Sakr S., Zomaya A. (eds) Encyclopedia of Big Data Technologies. Springer, Cham (2018)