escape sequence

gr8linux

escape sequence 033 is used with echo to change foreground and background colour and many effects........

i wanna know what is the significance of' 033 ...... and why we use here 033 ONLY..

dev/null

033 is octal representation for escape character (esc).

For Bash (and other shells), the foreground/background changes require the command to send escape characters before/after other codes, hence the use of 033.