Imagine you're trying to get a new job. You've sent a bunch fo resumes out and you've gone online. You've done everything you can, but you still haven't found something you're happy about. So you start working your social network. Who do you think'll be most useful to getting you a job, someone you know well or someone you know less well? It turns out that all our social ties don't find out about something when we do. In fact, information doesn't flow like water through an open channel between a social network. It requires active sharing. And so rather than thinking about social ties as bridges between islands, it's better to think of them as drawbridges for sharing information that can be either open or closed, depending on whether someone wants to pass something on. But importantly the flow also depends on the type of ties. There are two different types, strong ties and weak ties. How many people do you think you talk to at least once a week every week of the year? Well, it turns out you talk to about ten people, and these people are considered your strong ties. You can think about the same thing on Facebook. People have on average about 130 Facebook friends. By how many they interact with regularly? Well, by analyzing the photos and looking at who people show up with repeatedly over time, researchers find you show up between four to six friends repeatedly. Again, those are your strong ties. If you do this same thing with phone records, if you take a look at different people's phone records, you see that 80% of calls are to four people in their social network. And in all these cases these people are strong rather than weak ties. Strong ties are people you talk to often, you've known for a long period of time. They could be good friends, family members, or other people that you know quite well. Weak ties tend to be more casual relationships. People you talk to infrequently, acquaintances, or someone you bump into at the water cooler. So which of those types of ties would be more effective in helping us get a job? The strong ties, the people we know really well or the weak ties the people we don't know as well? Well, a number of years ago a sociologist studied exactly this. He looked at how people get jobs and he found that a lot of times people get jobs through their social ties. But he was interested in more than just that. He was interested in what type of ties people tend to get their jobs through. You might expect that our strong ties will be more useful in helping us get a job. They know us much better and they care about our interests more. Take your parents for example. Your parents know a lot about you and they wanna do everything they can to help you get a good job. In fact if you ever been set up on a date. You know that your parents are very motivated to help you get things done in your life. You may not expect that our friends, the people that know us well are similar to family members. They want to help us get a job and so they work hard to make it happen. You might think our weak ties could sort of care less. They don't know us as well and they don't care as much as about our interests. They shouldn't be very helpful in helping us get a job. But if you dug further, scientists realized that weak ties can actually be quite useful. In an article titled, the Strength of Weak Ties, he found that weak ties are actually much more helpful in getting people a job. And the reason, well counterintuitive, makes sense once you hear it. Weak ties have access to a lot different information than our strong ties do. If you remember that idea of homophily, the fact that we tend to be friends with similar others. Our friends tend to know us very well, but they also tend to pull from the same wells of information. Professors tend to hang out with professors, accountants tend to hang out with accountants, and art historians tend to hang out with other art historians. But because of that, the information they get is often redundant. Your friends, your colleagues, the people that know you very well have access to the same information that you do. Whereas, your weak ties tend to be different from you. You don't know them as well, but they tend to drill in different wells of information. And because of that, they have access to information you might not have already. And as a result, they can be much more effective in getting you a job And second, simply put, there are more of them. There are so many more weak ties that we have than strong ties. That even if each weak tie on average has a lesser effect per individual, because there are more of them they add up to have a big impact. Different types of ties not only shape whether or not we get a job. They also shape what we wear. Think for a moment on what we share with our stong ties versus what we share with our weak ties. What we share with people that we know very well versus what we share with people that we don't know as well. It turns out that if we don't know people as well, if someone is a weak tie, we're not gonna share as much information with them that we might share with a strong tie. If we don't know someone as well we are a little more worried about how we might look, how sharing a particular piece of information might make us come off. So we tend to share things that make us look good and tend to avoid sharing things that make us look bad. We don't share that embarrassing news story we read online or we don't tell that story about how we screwed up or picked a bad restaurant. Whereas with our strong ties we are more willing to be honest. We are more willing to disclose embarrassing things that we might not want those weak ties to know. Because strong ties know what's better, we're less worried how this one piece of information we share with them might make us look. But that is an important implications for getting information off violence because weak ties tend to bridge between islands that become very important in getting things to catch on. If people just a product or service among their strong ties, they're never gonna spread to different groups that might not be connected to that initial group. We need to make sure that weak ties are willing to carry the information to make sure it moves between different islands. While word of mouth may carry buzz and understanding the science behind word of mouth may help us make our messages more contagious, where messages go depend on the network. We need to understand how network structures and types of ties shape the spread of information and influence. And how that drives why all sorts of things catch on.