The ancestor of every action is thought; when we understand that we begin to comprehend that our world is governed by thought and that everything without had its counterpart originally within the mind.
The greatest investment a young person can make is in their own education, in their own mind. Because money comes and goes. Relationships come and go. But what you learn once stays with you forever.
Writing to offer a piece of information or a connection is a great way to demonstrate that you're looking out for the other person. Humans have a tendency to want to reciprocate, so the more you show you're looking out for someone, the more likely that person will begin to keep you in mind as well.