OCaml is an industrial strength programming language supporting functional, imperative and object-oriented styles. It is used as a "teaching language" by a lot of institutions. OCaml has a rich and powerful type system that allows the compiler to catch some mistakes early on saving the developer a huge amount of frustration. Type inference relieves the developer from the tedium of providing all the type signatures by themselves.
If you've downloaded the command-line client and have OCaml installed on your machine, then go ahead and fetch the first problem.
exercism fetch ocaml
In order to be able to submit your solution, you'll need to configure the client with your Exercism API key.
exercism configure --key=YOUR_EXERCISM_KEY
When you've written a solution, submit it to the site. You'll have to configure the command-line client with your exercism API key before you can submit.
exercism submit PATH_TO_FILE