Ubuntu is an African concept of coexisting with other people, of compassion, of responsibility to other people. Although it's not as widespread in the US, for example, as the Christian concept of charity, it crops up now and again, frequently in interesting places (such as the name for a linux interface). Watching this Global Oneness video is a good way to get a handle on the concept and appreciate this wonderful aspect of African culture.
I was especially caught by the man who talked about Ubuntu being a concept of extending one's self to others for equality. Sometimes in life, this will mean giving, and other times, it will mean asking for help. While both can be difficult, I've realized that I put a lot more effort into learning to give than learning to ask. I look for gifts for family and friends, or opportunities to lend a helping hand, such as when a friend is moving apartments. When someone on a street corner asks for money, I give them eye-contact, respect and a second of my time even when I don't have change.
Learning to ask for help, however, is just as important as learning to give in the process of creating community. I'll be the first to admit that I am frequently nervous to "impose" upon someone if I don't know them extremely well. But asking gives people a reminder that they are a responsible part of a larger world. By asking, you might be teaching them a way to help other people in your same situation. By asking, you may also be showing them that it's okay for them to ask when the need arises. And perhaps most importantly, by asking you start an interaction that gives you both a stronger connection to each other.