There are many options, each with its own features and limitations. For example, Smugmug is geared to professional photographers as it allows you to sell your images, while Shutterfly promotes printing your images in books, on mugs or other products. Some sites are free, but may include ads beside your photos. Others are accessible as a paid service with specific benefits.
Most sites allow you to organize your photos into groups, tag your images for easy searches, and provide you with a link that you can e-mail to friends or add to your blog. Some also provide apps for your smart phone or tablet to upload and manage your images. While some sites provide the option to restrict who can see an image, be aware that once an image is on the web it can be copied by someone with access and placed on other sites. To help protect your intellectual property, try watermarking your images so that they cannot be passed off as someone else's. More on that in a future article.
Let people know when you have uploaded images of them and, in most cases, they will thank you for sharing. Upload some images and pass around the warm feelings.