<s>
This	O
article	O
compares	O
variety	O
of	O
different	O
X	B-Application
window	I-Application
managers	I-Application
.	O
</s>
<s>
For	O
an	O
introduction	O
to	O
the	O
topic	O
,	O
see	O
X	B-Operating_System
Window	I-Operating_System
System	I-Operating_System
.	O
</s>
