How Google discovers pages (crawling) in SEO Fundamentals - Visual Walkthrough

Concept Flow - How Google discovers pages (crawling)

Start with known URLs

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Fetch page content

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Extract links from page

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Add new links to crawl list

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Repeat fetching next URL

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End when no new URLs

Google starts with known web pages, fetches their content, finds new links, adds them to the list, and repeats until no new pages are found.

Execution Sample

SEO Fundamentals

1. Start with seed URLs
2. Fetch page content
3. Extract links
4. Add new links to crawl queue
5. Repeat for next URL

This process shows how Google crawls the web by visiting pages and discovering new links step-by-step.

Analysis Table

Step	Action	Current URL	Links Found	New URLs Added	Crawl Queue State
1	Start with seed URLs	https://example.com	N/A	https://example.com	[https://example.com]
2	Fetch page content	https://example.com	https://example.com/about, https://example.com/contact	https://example.com/about, https://example.com/contact	[https://example.com/about, https://example.com/contact]
3	Fetch page content	https://example.com/about	https://example.com/team	https://example.com/team	[https://example.com/contact, https://example.com/team]
4	Fetch page content	https://example.com/contact	No new links	None	[https://example.com/team]
5	Fetch page content	https://example.com/team	No new links	None	[]
6	No more URLs	N/A	N/A	N/A	[]

💡 Crawl ends when no new URLs remain in the queue.

State Tracker

Variable	Start	After Step 2	After Step 3	After Step 4	After Step 5	Final
Crawl Queue	[https://example.com]	[https://example.com/about, https://example.com/contact]	[https://example.com/contact, https://example.com/team]	[https://example.com/team]	[]	[]
Current URL	N/A	https://example.com	https://example.com/about	https://example.com/contact	https://example.com/team	N/A
New URLs Added	N/A	https://example.com/about, https://example.com/contact	https://example.com/team	None	None	N/A

Key Insights - 3 Insights

Why doesn't Google crawl the same page multiple times?

Google keeps track of URLs already crawled and only adds new, unseen URLs to the crawl queue, as shown in the crawl queue state in the execution_table.

What happens if a page has no new links?

If no new links are found, no URLs are added to the queue, and Google moves on to the next URL until the queue is empty, as seen in steps 4 and 5.

How does Google find new pages to crawl?

Google extracts links from the content of each fetched page and adds any new URLs to the crawl queue, demonstrated in steps 2 and 3.

Visual Quiz - 3 Questions

Look at the execution_table at Step 3. What URLs are currently in the crawl queue?

A [https://example.com/about, https://example.com/contact]

B [https://example.com/contact, https://example.com/team]

C [https://example.com/team]

D []

💡 Hint

Check the 'Crawl Queue State' column at Step 3 in the execution_table.

At which step does the crawl queue become empty?

A Step 4

B Step 6

C Step 5

D Step 3

💡 Hint

Look at the 'Crawl Queue State' column to see when it becomes [].

If the page at https://example.com/team had a new link, what would change in the execution_table?

A New URLs would be added at Step 5 and the crawl queue would not be empty.

B The crawl would end earlier.

C No change, because new links are ignored.

D The crawl queue would empty at Step 4.

💡 Hint

Refer to how new links add URLs to the crawl queue in Steps 2 and 3.

Concept Snapshot

Google crawling starts with known URLs.
It fetches page content and extracts links.
New links are added to the crawl queue.
Process repeats until no new URLs remain.
This helps Google discover new pages on the web.

Full Transcript

Google discovers pages by starting with a list of known URLs called seed URLs. It fetches the content of each URL, looks for links on that page, and adds any new links to a queue to be crawled next. This process repeats, fetching pages from the queue, extracting new links, and adding them to the queue. The crawl ends when there are no more new URLs to visit. This method ensures Google finds and indexes many pages across the web efficiently.