For me it was playing Halo: Combat Evolved on the pc back in 2003. But I didn't fully get into online gaming until 2008. My friend introduce me to xbox live on the 360. At the time I didn't give a shit about the forums or playing online much. But my friend told me once I tried xbox live I will never be the same. He also told me that xbox live can be a cruel mean world, and that once I get into online gaming I will understand.
So I gave it a try first thing I had to do was pick my username. Every username I had in mind was already taken. So I let the 360 come up with a username for me and it was FalseRelic. I didn't care about the name but my friend thought it sounded original. So I picked the name and the first game I played was halo 3. I had a blast shooting up people, trash talking and tea bagging my victims.
Afterwards I tried out demos and bought games. Ever sense I've been online gaming. Then overtime I understood exactly what my friend meant about the online gaming world. It really can be a cruel place.