A track is the description of one ore more benchmarking scenarios with a specific document corpus. It defines for example the involved indices, data files and which operations are invoked. List the available tracks with esrally list tracks. Although Rally ships with some tracks out of the box, you should usually create your own track based on your own data.
A challenge describes one benchmarking scenario, for example indexing documents at maximum throughput with 4 clients while issuing term and phrase queries from another two clients rate-limited at 10 queries per second each. It is always specified in the context of a track. See the available challenges by listing the corresponding tracks with esrally list tracks.
A car is a specific configuration of an Elasticsearch cluster that is benchmarked, for example the out-of-the-box configuration, a configuration with a specific heap size or a custom logging configuration. List the available cars with esrally list cars.
Telemetry is used in Rally to gather metrics about the car, for example CPU usage or index size.
A race is one invocation of the Rally binary. Another name for that is one “benchmarking trial”. During a race, Rally runs one challenge on a track with the given car.
A tournament is a comparison of two races. You can use Rally’s tournament mode for that.