The EU network codes and guidelines are a detailed set of rules pushing for the harmonisation of national electricity markets and regulations. A total of eight network codes and guidelines entered into force by the end of 2017: three grid connection codes (RfG NC, DC NC and HVDC NC), three market codes (FCA GL, CACM GL and EB GL), and two operation codes (SO GL and ER NC). The major part of this text covers the market codes. The reader is guided through the sequence of electricity markets in place in the EU: forward markets, the day-ahead market, the intraday market and finally the balancing markets. The establishment of these different markets in a national context is discussed and their integration. Additionally, also two connection codes (RfG NC and DC NC) are discussed; the scope of theses codes is described and technical requirements are clarified. Where relevant, the link between the system operation guideline (SO GL) and the market or connection codes is made. In each section, basic market design or more technical concepts are explained, we highlight what is in the codes, and we also refer to some of the relevant academic literature.