In Go, channels are a powerful tool for communicating between goroutines, but they can be used in different ways depending on the requirements of the application. One important distinction to make is between buffered and unbuffered channels.
An unbuffered channel has a capacity of 0, which means that it can only hold one value at a time. When a value is sent on an unbuffered channel, the sender blocks until a receiver is ready to receive the value. This can be useful in situations where synchronization between goroutines is important, since it ensures that a sender and receiver are always available at the same time.
A buffered channel, on the other hand, has a fixed capacity and can hold multiple values. When a value is sent on a buffered channel, it is added to the end of the buffer if there is space available. If the buffer is full, the sender blocks until a receiver removes a value from the buffer, creating space for the new value. Buffered channels can be useful in situations where asynchronous communication is desired, since they allow for some buffering of messages.
In summary, unbuffered channels provide a way to ensure synchronization between goroutines, while buffered channels provide a way to decouple senders and receivers and allow for some buffering of messages.