Crawled — currently not indexed
A Search Console status meaning Google fetched a URL but chose not to index it, usually a quality, duplication or value judgement.
Crawling Indexing
Discovered — currently not indexed
A Search Console status meaning Google knows a URL exists but has not crawled it yet, typically because of crawl capacity or low crawl demand.
In full
Google reports this when a URL was found (via sitemap or link) and queued but deliberately deferred. It usually signals either that the site is slow enough that Google is throttling, or that Google does not consider the URL worth fetching. On large sites it is the clearest symptom of a crawl-demand problem: the remedy is fewer, better URLs, stronger internal links to the affected templates, and faster responses.
Example
A 500,000-SKU catalogue shows 180,000 URLs in 'Discovered — currently not indexed' while its top-selling 20,000 products index fine.
Related terms
Crawl demand
How much a search engine wants to crawl a set of URLs, driven by their popularity, how often they change, and the site's perceived overall…
Crawl budget
The number of URLs a search engine is willing and able to crawl on a site in a given period, set by crawl capacity limit and crawl demand.
URL Inspection tool
A Search Console feature showing Google's indexed state for a URL plus a live test with rendered HTML, screenshot, and page resource…
Internal linking
Links between pages on the same site, which control crawl paths, distribute link equity, and communicate topical relationships and page…