If your computer has a wireless card installed with an Ethernet connection, how can you make it a wireless router?

There is a very easy and straight-to-the-point program on internet called "mHotspot". enter it in your google and download. very easy to download and very easy to configure. the concept is internet source (ethernet)->broadcast/share(wi-fi card).

Dont forget to run it as administrator.

If you dont like to install the program, then i can make straight from the garage-type code which runs on command prompt of windows. I usually do this if im not sure or i dont trust a program.

By making it as a Hotspot (Tethering). It can be done by many ways. Not inclusively:

1- Setting up a Wi-Fi connection through the Windows Connection Wizard.

2- Making a Batch file that does this operation once ran and another batch to stop.

3- Downloading an App that does this operation

Just install a wifi-hot spot software on pc and do configuration..that's it ur pc will get as a virutal router..

Wireless router and wireless cards mostly do the same job but different connections. A wireless router is a network device that performs the functions of a router but also includes the functions of a wireless access point. A wireless card (also called a wireless adapter) is a hardware device designed for laptops or PCs, that enables your laptop/PCs to access high-speed, wireless networking within range of the wireless card.

Check this link for your answer: 

http://www.pcworld.com/article/249185/how_to_set_up_a_wireless_router.html

http://lifehacker.com/5369381/turn-your-windows-7-pc-into-a-wireless-hotspot

we can use ICS and some other sw

Installing software like connectify can utilise the wireless card as a router and share the ethernet card's network.

By sharing one of your network interfaces, through other interfaces

First of all, make sure the wireless lan is supported the Hosted Network, if yes, then you will be able to make a Wireless Access Point / Router.  You can check it by this command in cmd : netsh wlan show all.

If the hardware supported Hosted Network than you can setup Wireless Access Point with in the cmd with netsh command or you can use third party application like Baidu WiFi Hotspot: Download WiFi Hotspot

Asalam-O-alaikum wrwb Saqib bhai

In windows you can use3rd party software to enabale your laptop/desktop which have wlan card into a wifi hotspot. 

mHotspot (Free)

Conectify Hotspot Pro (Paid Softwware)

But in Ubuntu Linux you don't need any software, you have to just enable it.

simple with help of  connectify hot spot ..... still we can manipulate to connect no of users to access the network

Very easy , share the local network and allow in the setting to give resource to wireless adapter

then restart your PC , and it will be router.