怎么样实现一个矩形框？

怎么样用JAVASCRIPT画一个矩形框？？？？深期待中。。。。

---------------------------------------------------------------

应该不是楼上说的了,我有例子,不止矩形了

 1<body>
 2<script>   
 3if(IE4) {   
 4  
 5// 基本图形   
 6color = "maroon"   
 7Cir(50,40,20)   
 8Arc(100,40,20,60,120)   
 9Pei(150,60,40,240,300)   
10Rect(200,20,40,40)   
11  
12// 折线图   
13color = "#FF0000"   
14var jd = new Array(   
15203,232,277,223,271,234,273,284,276,250,267,280   
16)   
17MoveTo(30,jd[0]-40)   
18biaozhu(xo,yo,jd[0])   
19for(i=1;i<jd.length;i++) {   
20LineTo(i*30+30,jd[i]-40)   
21biaozhu(xo,yo,jd[i],1)   
22}   
23color = "#C0C0C0"   
24Line(30,140,i*30+30,140)   
25Line(30,140,30,260)   
26  
27// 饼图   
28color = "#00FF00"   
29var gc = new Array(   
30150,120,200,180,180   
31)   
32var s = 0   
33var m = 0   
34var n = 0   
35for(i=0;i<gc.length;i++) {   
36s +=gc[i]   
37if(gc[i] > m) {   
38m = gc[i]   
39n = i   
40}   
41}   
42var k = s/360   
43var mm = 0   
44var a =0   
45for(i=0;i<gc.length;i++) {   
46b = Math.round((gc[i]+mm)/k)   
47if(i==n)   
48PopPei(600,150,100,a,b)   
49else   
50Pei(600,150,100,a,b)   
51biaozhu(60,a+(b-a)/2,Math.round(gc[i]/s*100)+"%",2)   
52mm = mm+gc[i]   
53a = b   
54}   
55  
56// 十字标注   
57MoveTo(280,20)   
58zhunxing(xo,yo)   
59  
60}else {   
61document.write("<p> </p><table bgcolor=#FF0000><tr><td><font color=#FFFF00>对不起！您的浏览器不能支持该页的某些功能，请换用IE4.0以上版本的浏览器！谢谢！</font></td></tr></table>")   
62}   
63</script>
64</body>