How do people add you to their contacts?

How do people find me to add to their Messenger contacts?

• I get invited by strangers asking to add me to their Messenger contacts. How do they find my information to even send me this request?

• Answer:

  This is a form of spam. Do not accept these contacts - the links usually open to porn sites, and could contain malware. Spammers have programs especially to invent random e-mail addresses. Millions of spam mails are sent each day, usually from infected computers whose owners are not aware they are sending spam.