I use google to store and post my photos. It works very well for me.
You have 15 GB of free storage to share between Google Drive, Gmail, and Google+ Photos. Your storage use is based on which of the following items you’ve stored in these three products:
Gmail: All the messages and attachments in your mail, including those in Spam and Trash.
Drive: Files you’ve stored in Drive, like PDFs, images, and videos. Anything you’ve made with Docs, Sheets, and Slides won’t count towards your storage limit.
Google+ Photos: Only photos over 2048 x 2048 pixels and videos longer than 15 minutes count towards your storage limit.
Definitely X2 that - Google is the best all around free solution I have found on the 'net
Google (Picasa) web albums are my first choice because I can use my phone, tablet, and PC. If I have images on my camera, I always now upload them to Google web albums because as smokendevo mentioned, you can upload an unlimited number of pics as long as they are not larger than 2048x2048 - the good thing is that you can set the pics to automatically not exceed that limit. Quick snapshots on my phone or tablet are also automatically sent to my web albums.
I tried Photobucket a few times, and while it is adequate, I have often seen posts where there is a problem - unless you are logged in to photobucket, you cannot see the image when the thumbnail is clicked to see the original.