There are a few different types of trigger words that you can use with Alexa. The most common ones are Alexa, Echo, and Computer. You can also use Hey, Alexa or OK, Alexa as your trigger word. If you want to be more specific, you can say Play music from Pandora on my Echo or Turn on the living room lights.
You can also create custom wake words for your device. To do this, open the Alexa app and go to Settings > Device Settings. Select your device and then scroll down to Wake Word. From there, you can choose Custom and type in the word or phrase you want to use.