Neo4j is a graph database that uses Cypher as its query language. Developer Relations Engineer at Neo4j is sharing their knowledge on how to find the data types of properties in Neo4j, which they found was not straightforward and required searching documentation, Slack messages, and trial and error. The engineer explains that there are many data types available in Neo4j, including standard simple data types such as String, Integer, Float, Boolean, and DateTime, and that most of them match up to types available in other technologies. They also explain that the `type()` and `valueType()` functions in Cypher do not return the desired data type information, but rather a string representation of a relationship type or an expression's value type, respectively. The engineer then introduces two APOC library functions, `apoc.meta.cypher.type()` and `apoc.meta.cypher.types()`, which provide exactly what they were looking for: the data types of properties in Neo4j. These functions can handle single properties, multiple properties, or even lists of nodes as input, making them a valuable tool for developers working with Neo4j.