When making a phone call, if a call comes in, you can hold down the first call first, and the other party can hear the reserved music. You can talk to the second phone and then go back to the first phone.
The development function of the landline is relatively complete, and the function has almost reached high quality. The function of the callback key in the landline is quite common and very simple. It brings good news to those who missed answering the phone.
Extended data:
Other keys "#" and "*"
1. When the interaction between telephone and computer was first developed, because 0-9 only had 10 digits, it was arranged in the form of number × number. Whether it is 3×3 or 3×4, the arrangement is not neat. The final arrangement is 3×4, and the missing two spaces are occupied by "#" and "*" keys. Now the "#" and "*" keys have been given different special functions in different times.
2. The buttons on the landline are hidden. For example, you can use the * 55 * key combination to set the alarm clock time. If you want to set the alarm clock at 6: 30 in the morning, you can press * 55 * 0630 #. After the time is set, the phone will ring automatically. In addition to the alarm clock function, there are other functions such as checking mobile phone and dialing back, which also need to be completed by using the "#" and "*" keys.