What are the 4 ways of executing a shell script in Unix/Linux?

Q. 73. What are the 4 ways of executing a shell script in Unix/Linux?

1 - Use the filename to run the shell script 

$ /home/pbmac/scripts/myscript   (myscript is the file name)

2 - Specify the interpreter as a way to execute the shell script   

$ bash myscript    (bash is the interpreter)

3 - Using . ./ (dot space dot slash) to execute the shell script 

$ . ./myscript

4 - Using the source command to execute the shell script 

$ source ./myscript