Perplexity.ai

Perplexity AI is an AI chatbot-powered research and conversational search engine that answers queries using natural language predictive text. Launched in 2022, Perplexity generates answers using sources from the web and cites links within the text response. Perplexity works on a freemium model; the free product uses the company's standalone large language model (LLM) that incorporates natural language processing (NLP) capabilities, while the paid version Perplexity Pro has access to GPT-4, Claude 3.5, Mistral Large, Llama 3 and an Experimental Perplexity Model. As of early 2024, it has about 10 million monthly users.

History
Perplexity was founded in 2022 by Aravind Srinivas, Denis Yarats, Johnny Ho and Andy Konwinski, engineers with backgrounds in back-end systems, AI and machine learning. Yarats, the CTO, was an AI research scientist at Meta, while Srinivas, the CEO, worked at OpenAI as an AI researcher. Ho, the Chief Strategy Officer, worked as an engineer at Quora, then as a quantitative trader on Wall Street, and Konwinski was among the founding team at Databricks.

As of 2024, Perplexity has raised $165 million in funding, valuing the company at over $1 billion. Investors include Jeff Bezos, Nvidia, Databricks, Bessemer Venture Partners, Susan Wojcicki, Jeff Dean, Yann LeCun, Andrej Karpathy, Nat Friedman, and Garry Tan.

Functionality
Perplexity's main product is its search engine, which relies on natural language processing. It utilizes the context of the user queries to provide a personalized search result. Perplexity summarizes the search results and produces a text with inline citations. it allows users to ask follow-up questions that are interpreted in the same context.

Perplexity uses a freemium model and provides basic search functionalities and all search modes for free. The 'Focus' feature allows users to restrict the search to Reddit, YouTube, WolframAlpha or to restrict it to Academic (for searching research papers) or to Writing (Disables internet access for the LLM).

Perplexity's paid variant, the "Pro" mode (formerly Copilot), asks the user clarifying questions to refine queries. It enables users to upload and analyze local files, including images, alongside generating images using AI. Additionally, it provides access to an API. Perplexity launched a new enterprise version of its product in April 2024. In May 2024, Perplexity launched a new feature called Pages, which generates a customizable webpage based on user prompts. Pages utilizes Perplexity’s AI search models to gather information and create a research presentation that can be published and shared with others.

Use of content from media outlets
In June 2024, Forbes publicly criticized Perplexity for their use of Forbes' content. According to Forbes, Perplexity published a story which was largely copied from a proprietary Forbes article, without mentioning or prominently citing Forbes. In response, Srinivas said that the feature had some "rough edges" and accepted feedback, but maintained that Perplexity only "aggregates" rather than plagiarizes information.

Later that month, separate investigations by the magazine Wired and web developer Robb Knight found that Perplexity does not respect the robots.txt standard, which allows websites to stop web crawlers from scraping content, reportedly despite Perplexity claiming the opposite. Perplexity also lists the IP address ranges and user agent strings of their web crawlers publicly, but according to Wired and Robb Knight, they use undisclosed IP addresses and spoofed user agent strings when ignoring robots.txt. In response, Srinivas stated in a phone interview that "Perplexity is not ignoring the Robot Exclusions Protocol... We don't just rely on our own web crawlers, we rely on third-party web crawlers as well." Srinivas explained that the web crawler identified by Wired was owned by a third-party provider. Wired also stated that, in some cases, Perplexity may be summarizing "not actual news articles but reconstructions of what they say based on URLs and traces of them left in search engines like extracts and metadata, offering summaries purporting to be based on direct access to the relevant text." When asked whether Perplexity would cease scraping Wired content using third parties, Srinivas responded that "it's complicated."

Amazon Web Services, which hosts the Perplexity crawler, has a terms of service clause prohibiting its users from ignoring the robots.txt standard. Amazon began a "routine" investigation into the company's usage of Amazon Elastic Compute Cloud.