In computer programming, a script is defined as a sequence of instructions that is executed by another program. A shell is a command-line interpreter of Linux which provides an interface between the user and the kernel system and executes a sequence of instructions called commands. A shell is capable of running a script. A script that is passed to a shell is known as a shell script.

Bash script:

A Bash Script is just like a simple text file, consisting of a number of commands that we usually write in a command line. In Linux file systems, they are used for doing repetitive tasks. A Bash Script may contain a number of commands, or it might contain elements like loops, functions, conditional constructs, etc. In simple words, a Bash script is a computer program that is written in the Bash programming language.

Some of the features of Bash are given below:

• Bash can be invoked by single-character command-line options as well as multi-character command-line options. For example, (-a, -b) is a single-character command-line, and --debugger is a multi-character command-line option.
• Bash consists of Key bindings.
• Bash provides one-dimensional arrays with the help of which we can easily manipulate the lists of data.
• Bash provides control structures. For example, construct structure, etc.

Example:

#!/bin/bash  

myString="GeeksforGeeks"
echo "myString: $myString"

Output:

Shell script:

Shell is considered as a special user program that provides a platform or interface to users so that they can use operating system services. Users can provide human-readable commands to a shell and then shell convert them into kernel understandable form. A shell is considered a command language interpreter that can execute commands which can be read from input devices like a keyboard.

Some of the features of a Shell are given below:

• Wildcard substitution in file names (pattern-matching): To carry out commands on a bunch of files by mentioning a pattern to match rather than mentioning an actual file name.
• Background processing: To make lengthy tasks run in the background in order to free the terminal for concurrent interactive processing.
• Piping: To combine any number of commands together in order to form a complex program. The output of one program becomes the input of another command.
• Shell variable substitution: It stores the data in user-defined variables and predefined shell variables.

Now a shell can accept a number of commands through a file, known as a shell script. A shell script contains a number of commands that are executed by a shell.  For example, 

Example:

#!/bin/sh

myString="GeeksforGeeks"
echo "myString: $myString"

Output:

Table of difference between bash script and shell script

Conclusion

While Bash scripts and shell scripts are similar, they are not the same. A Bash script is a type of shell script, one that's specially tailored for the Bash (Bourne Again Shell) environment. A shell script, though, is a catch-all phrase — it's any script that runs in a shell, whether Bash, sh, csh, ksh, or another kind of shell.

If you're coding on Linux or Unix systems, recognizing the difference between Bash and shell scripting enables you to select the appropriate tool on the basis of compatibility, scripting requirements, and performance. Bash is more feature-rich, extremely programmer-friendly, and accommodates sophisticated scripting elements such as arrays, conditionals, and functions. Vanilla shell scripts (such as sh) are most suited for simple task automation and cross-platform portability.