Laughter is universal. All humans and cultures laugh.
Laughter is contagious.
Laughter isn't about humor. Only 20% of laughter is from jokes; it acts as a bonding experience.
Laughter denotes social status. The higher up someone is the less likely they are to laugh.
Tickle laughing is different than regular laughing.
Most online interactions are asynchronous and therefore afford a lot of opportunity for social bonding through laughing.
Synchronous communication online should lead to more bonding if it allows laughter.
You don't need joke to make people laugh. Normal interactions can create laughter naturally and more frequently.
Your laughing will make people laugh it is contagious.