The main difference between "choose" and "pick" is that "choose" typically implies a decision that requires some thought or consideration, while "pick" is often used to simply select something from a group of options without much deliberation.

For example:

I need to choose a new car to buy (implies a decision-making process based on various factors such as price, features, etc.)I'll just pick a random book from the shelf (implies a casual or arbitrary selection without much thought)

In general, "choose" is used for more deliberate or important decisions, while "pick" is used for more casual or random selections.