We should always introduce commenting scripts early in the piece. A script comment is prefaced with a # symbol. Anything after the # symbol is a comment and is not evaluated by the script. The shebang, #!/bin/bash, is primarily a comment and, as such, is not evaluated by the shell. The shell running the script reads the whole shebang, so it knows which command interpreter to hand the script over to. A comment may be at the start of a line or partway into the line. Shell scripting does not have the notion of multi-line comments.
If you are not already familiar with comments, then please note that they are added to the script to describe who wrote the script, when it was written and last updated, and what the script does. They are the metadata of the script.
The following is an example of comments in scripts:
#!/bin/bash
# Welcome to bash scripting
# Author: Mokhtar...