Linux / Unix: Shell Script Find Out In Which Directory Script File ResidesFrequently Asked Questions About Linux / UNIX

I need to find out in which directory my bash script resides so that I can read config file called .backup .ignore .target. For example, if my script resides in >/home/foo/script.sh, I need to read /home/foo/.{backup,ignore,target} files. How do I find out the current directory location and shell script directory location in Bash running on Linux or Unix like operating systems?

Read answer to: "Linux / Unix: Shell Script Find Out In Which Directory Script File Resides"