Console text question

[alvincent007]

Is there anyone can tell me what is the meaning of this

[xfpd]

See this link:

Variables and constants in RAM (global, static), used 29640 / 80192 bytes (36%)

This is only a report of how much memory your sketch uses. It is normal and expected and doesn't indicate any problem. Don't be alarmed by the red color of the text. Even though it is not an error message, the ESP8266 boards platform developers decided to print the report on the "standard error" stream (AKA "stderr") instead of the "standard output" stream (AKA "stdout"). Because the stderr stream is typically used only for warnings and errors, Arduino IDE colors text received from this stream…