What is Picasa

Update: Google finally retired Picasa-web-albums in mid 2016. The following article was correct until that time. Now, it is still possible to install the Picasa desktop software onto your PC, but Picasa-web-albums has been replaced by Google Photos and Google Album Archive.

Picasa is Google's tool for managing image files. This basic explanation of how it works is especially useful for new Blogger users who need to understand where pictures that they load to their blog are kept.

Picasa is Google's tool which people can use to manage and share image files (especially photographs) that they own or have the right to make copies of.

Picasa has three parts:

An application program ("Picasa") that you download, install and run on your PC. It works with the files store on your computer.
Picasa-web-albums (PWA): a place on the internet where you can store and share photos
Another application program (Picasa-web) that lets you manage photos stores in Picasa-web-albums. This software (like Blogger) runs totally inside your web-browser, and you don't ever have to download or install it.

The Picasa application program has an Upload button which lets you transfer copies of pictures from your PC to your Picasa-web-albums.

Your Picasa-web-albums are owned by your Google account - the same Google account that you use for Blogger, and various other Google tools.

Why Use Picasa-web-alblums

It's how Blogger works

When you write a post in Blogger, it looks like you can upload pictures - and before 2006, this was how things worked.

But when Google took over Blogger, they saw that it was silly for them to have two different places for storing pictures. So they set things up so that pictures uploaded in Blogger are stored in a Picasa-web-album.

And they added some features in Blogger so that as well as uploading pictures from your PC, can you also just choose ones that are already in Picasa-web-albums, and use them in your blog without making a second copy.

Photo sharing

Even people who aren't writing blogs want to share photographs with their friends. Doing this by email gets cumbersome if you have a lot of photos, and can use a lot of space. A better alternative is to put the photographs in a place on the internet, set up the security so that you control who can see them, and then tell your friends where to find them.

Many on-line services for doing this have been developed - Picasa is Google's version. (Google Inc, the company, not google search.)

On-line backup

Keeping a copy of your photos on-line is one way to ensure you have access to them even if something goes wrong with your PC (eg it crashes or is stolen). Picasa is an option for this, but you should be aware that the copy stored in Picasa-web-albums may not have as much file-size as the original picture if it was uploaded through Blogger.

Personally, I always upload pictures through PWA, and then use links to them from Blogger, so that I can resolution of the pictures that are in my albums.