what type of hardware i need.I got my Desktop PC and wireless
internet.I also have laptop.I want to connect this wireless internet
to my desktop and to laptop.Laptop already have wireless internet
adaptor and desktop doesnt have any.Can i catch waves by  wireless
router and that router can i joint to desktop by ethernet ?then this
same router can i connect to laptop by wireless application.In future
if i dont have wireless net then still  can  i use such hardware for
broadband internet through cable.?what kind of hardware i need?

Hi naresh999-ga,

To connect desktop to wireless network  you have the following options
a) PCI Card
(or)
b) If you have USB 2.0 ports on your desktop you can buy "USB 2.0
Wireless adapter". By just inserting the usb 2.0 adapter to one of
yours desktop usb ports, your desktop can communicate wirelessly with
your router.

Step#2
--------
buy Wireless router (3 in 1 router). This router will having 4 or 5
ethernet ports. So this will help you to connect to internet either
via wireless or via wired. Cable goes to your cable modem. Cable
modem's ethernet cable goes to your WIRELESS router. From there you
can configure wired/wireless network to your system.
There are excellent wireless security features available on these
routers. There are MAC filter, firewall filter at router level,
WEP/WPA encryptions etc.

Suggestions
---------
1) Make sure you have all infrastructure  from same vendor to avoid
incompatibilities whatever in the future. For example LINKY SYS,
NETGEAR, DLINKS etc. - I recommend LINK SYS

2) I suggest you go for 108.11a/g. 108.11b wireless will be vanishing
soon or later. What does it mean to you?. You want to buy a WIRELESS
ROUTER that supports 108.11 a/g. I DON'T SUGGEST you to guy 108.11
a/b/g routers (they are out there) unless your existing devices are
dependent 108.11b.

You can look in the following websites

a) buy.com
b) amazon.com
c) newegg.com
d) ebay.com
Let me know if you have any q's. best of luck