Python Data Analysis Cookbook

Running multiple threads with the threading module

A computer process is an instance of a running program. Processes are actually heavyweight, so we may prefer threads, which are lighter. In fact, threads are often just subunits of a process. Processes are separated from each other, while threads can share instructions and data.

Operating systems typically assign one thread to each core (if there are more than one), or switch between threads periodically; this is called time slicing. Threads as processes can have different priorities and the operating system has daemon threads running in the background with very low priority.

It's easier to switch between threads than between processes; however, because threads share information, they are more dangerous ...