In addition to the excellent writeups from both codic
, I'd like to point out a couple of things.
It's a great start to undertake some martial arts training, be it karate, boxing, aikido or muay thai. The form of training you start will vary entirely on the you and your needs. While blending ideas from various different styles is a great way to move towards being a "complete" fighter, there are a couple of important points to note:
First: You can't learn any system in a couple of months. If you're doing karate don't expect to be able to throw anything close to a decent roundhouse kick unles you're prepared to practice a lot.
Codic writes that he studied for two years. I would contend that after two years in only one style you might be starting to approach something resembling proficency. This will of course depend on what you are training in.
In short, be prepared to train a lot, for a long time before you can consider yourself even close to proficient. After six years of karate and muay thai training, there are still plenty of guys in the dojo who are more than capable of giving me a resounding ass-kicking.
Second: Sparring is not the same as a real-life street confrontation. As Codic's writeup notes, getting into a 'fight' with another individual is a definite start. It's only a start though, because although you may feel confronted, scared and very aware of your limitations as a fighter, it is not even close to the real thing.
It varies again from individual to individual. Your sparring partner is not going to beat you to a bloody pulp for the simple reason that most sparring sessions are in a controlled environment. That's the key. Real life street fights are not controlled environments. They're not a bully trying to steal your lunch money.
Finally: Don't give yourself a "false assumption of personal safety". As codic wrote - this is vital. Don't think you know it all no matter how hard and how long you've been training.
The longer I train the more I realise how much more I have to learn when it comes to confrontation, and the more I see the importance of seeking to avoid it at all costs.
Despite all you learn, all the years of training and all the skills you possess there will always be someone who has trained longer, knows more and has less to lose than you. Keep that in mind at all times. It might just save your life.