What are the differences between the types of channels in Go?

In Go, channels are of three types based on data transfer direction:

1. Bidirectional channels — regular channels that can be used for both sending and receiving data.

ch := make(chan int) // bidirectional channel
ch <- 10             // send
val := <-ch          // receive

2. Send-only channels — declared with the direction chan<-, allowing only sending data, receiving from them is impossible.

var sendOnly chan<- int = ch
sendOnly <- 5        // sending is allowed
// val := <-sendOnly // compile error

3. Receive-only channels — declared with the direction <-chan, allowing only receiving data, sending is prohibited.

var recvOnly <-chan int = ch
val := <-recvOnly    // receiving is allowed
// recvOnly <- 5    // compile error

Using directional channels helps improve type safety and makes the code more readable by explicitly indicating where the channel is used only for sending or receiving.