If you are given the IP address can u tell how many computers can be connected?What do you look at?

Yes: we look at its subnet mask and class ie. for eg: IP adress:161.172.0.10 is given. First we have to identify its class; there are 5 IP classes

1. classA{1-126.0.0.0}{subnet mask:255.0.0.0}
2. classB{128-191.0.0.0}{subnet mask:255.255.0.0}
3. classC{192-223.0.0.0}{subnet mask:255.255.255.0}
4. classD{224-239.0.0.0}{subnet mask:255.255.255.0}{Multicast IP; used fro applications like video conferencing}
5. classE{240-255.0.0.0}{subnet mask:255.255.255.0}{reserved for researches}

In the above classes our IP falls in the second catogory that is Class B; by looking to subnet mask we can have 2 portions;1.network 2.host{network portion is always One(1111 1111=255) and host portion is zero(0000 0000)}

so we have 16 zeros as host portion hence 2^16=65536 computers canbe connected to this class.