In Python, the difference between a multi-thread and a coroutine is the way they execute their code and manage concurrency.

A multi-thread is a traditional way to handle concurrent execution of multiple tasks by creating multiple threads that run in parallel. Each thread runs its own separate piece of code, and the operating system schedules their execution. This makes it well-suited for tasks that require parallel execution, but can be challenging to use effectively due to the difficulties of managing shared resources and coordinating communication between threads.

A coroutine, on the other hand, is a lightweight concurrency construct that allows multiple functions to be executed in a cooperative manner. In a coroutine, the code is executed one step at a time, and each function voluntarily yields control to the next function when it's ready. This makes it easier to manage concurrent execution, as there is no need for locks or other synchronization mechanisms. However, coroutines are less suited for tasks that require true parallel execution, as they only run one function at a time.

In conclusion, multi-threading and coroutines both provide mechanisms for handling concurrency in Python, but they have different strengths and use cases. Multi-threading is well-suited for parallel execution, while coroutines are better for cooperative execution and are easier to manage.