openCypher is the most widely adopted, fully-specified, and open query language for property graph databases. It provides an intuitive way to work with property graphs.
openCypher language enables users to perform standard database operations by using the following clauses:
MATCH, which searches for patterns;
WHERE, for filtering the matched data;
RETURN, for defining what will be presented to the user in the result set;
CREATE, for creating new nodes and edges;
SET, for adding new or updating existing labels and properties;
DELETE, for deleting nodes and edges;
REMOVE, for removing labels and properties;
MERGE, for creating patterns if they do not exist;
WITH, for combining multiple reads and writes.
openCypher supports a large number of functions. The list can be found here: openCypher Functions.