Wi-Fi Protected Access (WPA) is a security protocol that addresses weaknesses found in the preceding system WEP with both types of products being able to interoperate. This protocol incorporates the stable parts of the 802.11i security standard that is a work in progress.
After going through proof of concept and applied public demonstrations WPA showed some weaknesses and just like WEP was susceptible to intrusion.
You should use WPA2 whenever possible, and only use WPA in those cases when it is not supported by an access point. Sometimes a network speed may be affected by WPA2 usage, and then WPA also becomes an option, however it would be much more appropriate for the network security to upgrade access points. When none of the WPA standards can be used, then using WEP is possible.
UPD: WPA3 is the next-generation security protocol absolutely worth your attention. WPA3 provides better security and even saves you from your own security shortcomings.
What a WPA3 standard will offer once widely introduced:
Back in 2004 when WPA2 was introduced Internet was different, it changed a lot since then. Currently WPA2 doesn't feature a reliable way to onboard new devices to a wireless network. The Wi-Fi Protected Setup method has known issues since 2011 and needs a fix. WPA3 promises to provide it.
The Wi-Fi Alliance product Wi-Fi Easy Connect allows users to onboard devices without or with a limited screen or input options. This method simplifies onboarding significantly because you need to just scan a QR code on your router and a device and everything else will be done automatically. When you scan a QR code you are using a public key-based encryption thus connecting devices that lack secure mechanisms otherwise.
The newly implemented Wi-Fi Certified Enhanced Open program offers great new advantages to the users of open wireless networks. It's not news that open Wi-Fi networks are not compatible with safe browsing, so it was never recommended to enter any sensitive data while on an open network. You probably know that it was because of the WPA2 protocol vulnerability - anyone on the same network as you can get access to your online activity and initiate attacks. Once you can use WPA3 on a public Wi-Fi network, your connection will be automatically encrypted thanks to the "Opportunistic Wireless Encryption" standard.
Password is the first and foremost thing you should think of when considering your Wi-Fi network security. We do not recommend using lazy easy to hack passwords in any case, but surely WPA3 will minimize the damage.
WPA3 protocol introduces the new key exchange process protecting you from dictionary attacks that are so popular with WPA2. Dictionary attack is when hackers simply run a process of going through every word and combination from the dictionary and eventually cracking a lazy typical password.
Another weakness of WPA2 - the usage of four-way handshake between clients and access points - will be eliminated in WPA3 with its secure and reliable Simultaneous Authentication of Equals handshake.
Even if your password gets compromised while using WPA3, your data should remain safe thanks to the protocol's forward secrecy. This basically means that all traffic sent and received before the attack is encrypted and remains to be. In case of WPA2 previous traffic was not encrypted and attackers could easily get hold of the information.