The search giant, which debuted a website for the photo project on Wednesday, said it was able to categorize over 4 million iconic Life Magazine photographs without human help. After clicking on a particular label like “skateboarding,” for example, users are shown photos of people performing skateboard tricks along with Wikipedia’s definition of the sport.

Google uses deep learning technology to help its computers better understand objects like dogs or cats in pictures and make its image search tool more efficient to people wanting to see a particular image.

Compared to the core Google search, the photo project’s website is slow to load, especially when there are thousands of images assigned to a particular label like “road.”

Although Google has hosted a Life Magazine archive since 2008, the new website makes using it easier. Searching Life Magazine’s photojournalism for ballet brings up relevant photos alongside the name of the photographer who took the picture, the title of the photo like “Nutcracker Ballet,” and what in the photo Google’s computers were able to recognize, like a dancer.

Although usually accurate, Google’s technology does have some hiccups that highlight some of AI’s current limitations. For instance, under the “skateboarding” label is a photo that is shown sideways of a man wearing a top hat and holding a cane who is performing what looks like a campy musical number. For unknown reasons, the computers mistakenly thought it saw a skateboard in the image.

Additionally, the computer that created the index has come up with some odd categories that human editors likely wouldn’t have. One such label is “identity document,” which brings up photos of people’s passports and railroad tickets as well as a photo of musician Paul McCartney holding a Grammy plaque. It’s likely the computers saw similarities between a typical document and McCartney’s Grammy plaque, which in this case resembled more of a small, commemorative plate than the conventional 3-dimensional Grammy statue.

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Another label, “concrete,” highlights thousands of photos, some of which appear random. There’s a picture of an old tombstone, a photo of a marine boot camp, a picture of a person hunting a snake in a small enclosure, and a photo of the “Roosevelt Raceway” that shows a man—incorrectly identified by the computer as a fisherman— sweeping. While there indeed seems to be some sort of concrete object involved with each photo, it’s still an unconventional way to group all the pictures together considering they are displaying very different subjects.

In addition to the misidentified photos, the technology also failed to create labels for some obvious topics. They include some of Life Magazine’s most iconic photos.

For instance, the computers did not create a label for the “Vietnam War,” a subject that should include some of Life Magazine’s best known and most powerful photos. The computer did create is a “war” label, but it appears to have grouped over 23,000 photos, making searching for a particular picture difficult.