# Bash strings comparison

Here are a few ways to compare two strings in Bash:

    Using the equality operator (=):

```
bash
if [ "$string1" = "$string2" ]; then
  echo "Strings are equal"
else 
  echo "Strings are not equal"
fi
```

    Using the double bracket syntax:

```
bash
if [[ "$string1" == "$string2" ]]; then
  echo "Strings are equal"
else
  echo "Strings are not equal" 
fi
```

    Using the inequality operator (!=):

```
bash
if [ "$string1" != "$string2" ]; then
  echo "Strings are not equal"
else
  echo "Strings are equal"
fi
```

    Case-insensitive comparison:

```
bash
if [[ "${string1,,}" == "${string2,,}" ]]; then
  echo "Strings are equal (case-insensitive)"
else
  echo "Strings are not equal (case-insensitive)"
fi
```

    Checking if one string contains another:

```
bash
if [[ "$string1" == *"$string2"* ]]; then
  echo "string1 contains string2"
else
  echo "string1 does not contain string2"
fi
```

Key things to remember:

    Always quote your variables to handle spaces and special characters
    Use double brackets [[ ]] for more advanced comparisons
    The = operator works in single brackets [ ], while == is preferred in double brackets [[ ]]
    For POSIX compatibility, use single = even in double brackets