>
> s1 = s2 True if the strings s1 and s2 are identical.
>
> s1 != s2 True if the strings s1 and s2 are not identical.
>
> s1 < s2 True if string s1 comes before s2 based on the ASCII value
> of their characters.
>
> s1 > s2 True if string s1 comes after s2 based on the ASCII value
> of their characters.
>
> Nicholas Clark
>
Hmm... Well, 'man bash' says
== != equality and inequality
& bitwise AND
^ bitwise exclusive OR
| bitwise OR
&& logical AND
|| logical OR
But it seems that '=' works as well. I bet '==' is a bash extension...
