diff --git a/pysh.py b/pysh.py
index ebf980d..6770430 100644
--- a/pysh.py
+++ b/pysh.py
@@ -3,6 +3,7 @@
 import os
 import subprocess
 from utils.commands_list import *
+from utils.boyer_moore_algorithm import BoyerMooreAlgorithm
 import calendar
 import getpass
 import shutil
@@ -627,6 +628,24 @@ def do_diff(self, *args):
         else:
             print("pysh: diff: incorrect usage: try 'diff [FILE1] [FILE2]'")
 
+    def do_grep(self, *args):
+        commands = args[0].split()
+        self.save_history("grep " + " ".join(commands))
+        pattern = BoyerMooreAlgorithm(commands[0])
+
+        if '-f' in commands:
+            if os.path.exists(os.getcwd() + '/' + commands[commands.index('-f') - 1]):
+                with open(commands[commands.index('-f') - 1], 'r') as file:
+                    line_number = 1
+                    for line in file:
+                        pattern.find_pattern(line.split(' '), True, line_number)
+                        line_number += 1
+            else:
+                print("pysh: grep: {}: No such file or directory".format(commands[commands.index('-f') - 1]))
+        
+        else:
+            pattern.find_pattern(commands[1:])
+
     def do_chmod(self, *args):
         gen_args = args[0].split()
 
@@ -788,6 +807,9 @@ def help_kill(self):
     def help_diff(self):
         print(commands_list_manual['diff'])
 
+    def help_grep(self):
+        print(commands_list_manual['grep'])
+
     def help_chmod(self):
         print(commands_list_manual['chmod'])
 
diff --git a/utils/boyer_moore_algorithm.py b/utils/boyer_moore_algorithm.py
new file mode 100644
index 0000000..210c255
--- /dev/null
+++ b/utils/boyer_moore_algorithm.py
@@ -0,0 +1,65 @@
+from colorama import Fore
+
+NO_OF_CHARS = 256
+
+class BoyerMooreAlgorithm():
+    def __init__(self, pattern):
+        self.pattern = pattern
+        self.shift_table = [-1] * NO_OF_CHARS
+ 
+    # Fill the actual value of last occurrence
+        for char in range(len(pattern)):
+            self.shift_table[ord(pattern[char])] = char;
+
+    def find_pattern(self, source, file = False, line_number = 0):
+        source = " ".join(source)
+        pattern_length = len(self.pattern)
+        result = []
+        source_index = 0
+        while(source_index <= len(source) - pattern_length):
+            j = pattern_length - 1
+    
+            '''
+                Keep reducing index j of pattern while
+                characters of pattern and text are matching
+                at this shift source_index
+            '''
+            while j >= 0 and self.pattern[j] == source[source_index+j]:
+                j -= 1
+    
+            '''
+                If the pattern is present at current shift,
+                then index j will become -1 after the above loop
+            '''
+            if j < 0:
+                result.append(source_index)
+                '''   
+                    Shift the pattern so that the next character in text
+                    aligns with the last occurrence of it in pattern.
+                    The condition source_index + pattern_length < len(source) is necessary for the case when
+                    pattern occurs at the end of text
+                '''
+                source_index += (pattern_length - self.shift_table[ord(source[source_index + pattern_length])] 
+                                    if source_index + pattern_length < len(source) else 1)
+            else:
+                '''
+                Shift the pattern so that the bad character in source text
+                aligns with the last occurrence of it in pattern. The
+                max function is used to make sure that we get a positive
+                shift. We may get a negative shift if the last occurrence
+                of bad character in pattern is on the right side of the
+                current character.
+                '''
+                source_index += max(1, j - self.shift_table[ord(source[source_index+j])])
+
+        if file and result != []:
+            print(f"Line {line_number}: ", end = '')
+
+        previos_index = 0
+        for index in result:
+            print(source[previos_index:index], end="")
+            print(Fore.CYAN + source[index:index + len(self.pattern)] + Fore.RESET, end = "")
+            previos_index = index + len(self.pattern)
+
+        if result != []:
+            print('\n')
diff --git a/utils/commands_list.py b/utils/commands_list.py
index b49ce45..7560a6a 100644
--- a/utils/commands_list.py
+++ b/utils/commands_list.py
@@ -1,8 +1,7 @@
 commands_list = ['lf', 'ldir', 'pwd', 'cd', 'manual', 'mkdir',
                  'calendar', 'calc', 'whoami', 'echo', 'rm',
                  'cat', 'cp', 'mv', 'date', 'file', 'history',
-                 'head', 'tail', 'touch', 'wc', 'ip', 'host', 'arch', 'ps', 'wget', 'kill', 'diff',
-                 'chmod']
+                 'head', 'tail', 'touch', 'wc', 'ip', 'host', 'arch', 'ps', 'wget', 'kill', 'diff', 'chmod', 'grep']
 
 commands_list_manual = {
     'exit': "Exits the shell where it is currently running. \nusage: 'exit'",
@@ -36,5 +35,6 @@
     'wget': "Network downloader - download files from internet. \nusage: 'wget [URL]'",
     'kill': "Terminate an unresponsive program. \nusage: 'kill [PID]'",
     'diff': "Compares files line by line. \nusage: 'diff [FILE1] [FILE2]'",
+    'grep': "Utility for searching plain-text data sets for lines that match a regular expression. \nusage: 'grep [expression] [data-set] -f' {if the data-set is a file}\nusage: 'grep [expression] [data-set]' {if the data-set is an input string}",
     'chmod': "Changes access permissions and the special mode flags of file system objects. \nusage: 'chmod [PERMISSIONS] [FILES]...'"
 }