What does exclamation mark in triangle mean ?

[AC Question]

huawei 8850 does not appear to be charging and displays yellow exclamation mark in warning triangle.

it is not responding to power on button even when plugged in

 

[B. Diddy]

Welcome to Android Central! Could be a problem with the battery, the charging port, the charging cable, or the wall plug. The easiest things for you to try right now are to use a different cable and/or plug.