If you start to do something, you do something that you were not doing before and you continue doing it.

When something starts, or if someone starts it, it takes place from a particular time.

If you start by doing something, or if you start with something, you do that thing first in a series of actions.

You use start to say what someone's first job was. For example, if their first job was that of a factory worker, you can say that they started as a factory worker.

When someone starts something such as a new business, they create it or cause it to begin.

If you start an engine, car, or machine, or if it starts, it begins to work.

If you start, your body suddenly moves slightly as a result of surprise or fear.

You use for a start or to start with to introduce the first of a number of things or reasons that you want to mention or could mention.

If you get off to a good start, you are successful in the early stages of doing something. If you get off to a bad start, you are not successful in the early stages of doing something.

To start with means at the very first stage of an event or process.