French kissing is kissing with tongues, and considered by many to be more intimate and sensual than kissing without tongues. The name 'French kissing' is reported to come from the 20th Century, when the French were known as being more passionate than other nations. They have a reputation as 'lovers', hence the fact it can also be referred to as a lover's kiss. In the UK and Ireland, it might also be called a snog.
It may seem like an odd thing to say to some of you, but if you are looking to try some French kissing you will need to make sure you're prepared. Your lips may be dry and your breath may not be as minty-fresh as you are hoping it to be. Start by drinking some water - this will help to hydrate your lips properly to help keep them in the ideal state for kissing. If you find the water doesn't help enough, use some chapstick or lip-balm.
Freshening your breath is also essential, so make sure you add some mouthwash or breath mints to your dental hygiene routine to ensure your partner gets a pleasant and minty kiss, instead of the coffee you had on your way over from work.
Technique is extremely important when French-kissing. While you might want to dive straight in, it is best to start slowly and build up. Jamming your tongue down your partner's throat isn't pleasant and can be a huge turn-off, so keep it shallow and light at first. Follow your partner's lead - if they want to move things on then let them, but if they are happy to continue as you are doing don't push them. Again, this can be a turn-off. Read their body language and see what they like and dislike about the kiss. Listening can really help you to make it as passionate a kiss for your partner as you can.