Outdated Drivers Are Slowing You Down
One free scan finds every outdated or missing driver and matches the right update for your exact hardware.Free scan · exact hardware matchPC Slower Than It Used to Be?
A free scan shows the junk files, broken settings and background clutter dragging Windows down - then fixes them in one click.Free scan · Windows 10 & 11A web crawler discovers URLs, fetches selected pages, and may follow links to find more. To crawl a small site yourself, start with seed URLs, keep a queue and a set of visited URLs, fetch pages within a defined scope, extract links, and apply conservative request limits. For search engines, crawling is only one stage: a fetched page is not automatically indexed or shown in results.
What is a web crawler?
A web crawler—also called a bot, robot, or spider—is software that automatically discovers and fetches web resources. There is no central registry of every page on the web. Google says it must continually look for new and updated pages and add them to its list of known pages. Google’s guide to how Search works describes discovery through known URLs, links, and sitemaps.
Crawling, indexing, and serving results are separate stages. Crawling means retrieving a URL; indexing means processing and potentially storing its content; serving means selecting results for a search. A fetch does not guarantee indexing or visibility in results. Google’s explanation of Search distinguishes these stages.
How does a web crawler work?
A useful small-crawler model is a queue of URLs to consider and a record of URLs already seen. This is an implementation pattern for learning, not a universal architecture used by every crawler.
What’s actually slowing this PC down?
Pick the symptom - the matching free tool is one click away.
#1 Best Overall
- Read Before You Buy — No Video Output: These adapters support charging and USB 2.0 data transfer, but cannot transmit video signals. Except for standard USB webcams (which use USB data only), they are not compatible with HDMI/DisplayPort cables, video-capable USB-C hubs, or docking stations with video output.
- Convert USB-A Ports to USB-C: Designed to connect USB-C earphones, cables, flash drives, card readers, and other USB-C accessories to standard USB-A ports. Plug-and-play with no drivers or software required.
- Aluminum Alloy Housing: Built with a sturdy aluminum alloy shell that aids in heat dissipation and protects against daily wear and scratches. Designed to maintain a stable and secure connection.
- Compact & Travel-Friendly: The ultra-compact design allows the adapter to stay plugged into your device without blocking adjacent ports or adding bulk, reducing wear and tear on your original USB ports.
- 12-Month Warranty: Backed by a 12-month manufacturer warranty for peace of mind. Designed to meet strict quality control standards for reliable everyday performance.
- Choose seed URLs. These are starting pages supplied by you or another discovery source.
- Check eligibility. Confirm the URL is within your crawl scope, permitted by your rules, and not already seen.
- Fetch the page. Request it over HTTP, handle the response, and limit concurrent requests and request frequency.
- Parse what you need. Extract text, metadata, or links based on the crawler’s purpose.
- Normalize and deduplicate links. Resolve relative links, apply scope and access rules, and add eligible unseen URLs to the queue.
- Stop deliberately. Finish when the queue is empty or a defined boundary is reached, such as a page cap or crawl depth.
Production search crawlers may use different scheduling, rendering, parsing, and storage systems. The queue model is useful because it makes the essential decisions explicit: what to visit, what to fetch, and when to stop.
How do crawlers discover URLs?
Known URLs and links
A crawler can begin with URLs it already knows, then discover additional URLs in links on fetched pages. A page’s link structure can therefore help a crawler find pages that are not listed elsewhere.
Sitemaps
An XML sitemap lists URLs for crawlers to consider. It can help surface important pages, but inclusion does not guarantee a fetch or indexing. If you use a sitemap, keep it current; Google recommends including a lastmod value when content has been updated. See the Google sitemap guide and the Sitemaps Protocol.
How to crawl a website with a small custom crawler
For a basic crawler, choose one host and a modest page limit, use an HTTP client and HTML parser, and avoid crawling pages that require login or other authorization unless you have permission. A production crawler needs robust handling for redirects, response codes, retries, timeouts, URL normalization, and content types; the outline below describes the control flow rather than a complete production implementation.
Quick wins for a faster PC:
Repair Windows errors before they cause bigger problemsFix Now →Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →Rank #2
- 5-in-1 USB-C Hub: Experience comprehensive connectivity featuring a Power Delivery input, two USB-A 2.0 ports, a USB-A 3.0 port, and an HDMI port. (Note: The USB-C power delivery input port is only for connecting an external wall charger to power your laptop and cannot power peripheral devices.)
- 90W Pass-Through Charging: Achieve optimal charging with 90W pass-through power to your laptop, supported by a total input of 100W, with the hub reserving 10W for operational efficiency. (Note: Wall charger not included.)
- Quick Data Transfers: Accelerate your productivity with rapid data transfers using a high-speed 5Gbps USB 3.0 port and two 480Mbps USB 2.0 ports.
- 4K HDMI Display: Enhance your visual experience with a hub capable of delivering 4K resolution at 30Hz in both mirror and extend modes. Please note that this hub is compatible with MacBook (macOS 12 and newer), Windows 10 and 11, ChromeOS, and laptops equipped with DP Alt Mode and Power Delivery. Note: This device is not compatible with Linux.
- What You Get: Anker USB-C Hub (5-in-1, 4K HDMI), welcome guide, 18-month warranty, and our friendly customer service.
- Define the boundary. Decide which host, paths, and page types are in scope, and set a maximum number of pages.
- Seed the queue. Add one or more starting URLs, optionally informed by a sitemap.
- Fetch cautiously. Use limited concurrency and a delay or backoff policy. Do not assume one fixed request rate is safe for every site.
- Inspect responses. Handle redirects and errors; do not treat every response as a valid HTML page.
- Extract and enqueue links. Resolve relative links against the fetched page, normalize URLs consistently, and add only in-scope unseen URLs.
- Record results and stop. Track visited URLs and outcomes so you can avoid repeat work and understand failures.
Google says its crawlers try not to fetch so quickly that they overload a site; server responses such as HTTP 500 errors can prompt them to slow down. For your own crawler, conservative concurrency and backoff are safer than copying a guessed universal rate. See Google’s crawler documentation.
What does robots.txt do—and what does it not do?
The Robots Exclusion Protocol (REP), commonly published as /robots.txt, lets site owners express which paths compliant crawlers may access. It is a crawler instruction, not an access-control mechanism. The standard is documented in IETF RFC 9309.
Google fetches and parses robots.txt before crawling a site. The file belongs at the site’s top level and its rules apply only to the matching protocol, host, and port. Google’s supported fields include user-agent, allow, disallow, and sitemap; Google does not support crawl-delay. See Google’s robots.txt guide and its robots.txt specification guidance.
A disallowed URL can still appear in Google Search if other pages link to it, even when Google has not fetched its content. To keep information private, use authentication or another access-control mechanism. To prevent eligible content from appearing in Google Search, Google’s guidance points to options such as noindex or password protection rather than relying on robots.txt alone. See Google’s robots.txt introduction.
Rank #3
- Sleek 7-in-1 USB-C Hub: Features an HDMI port, two USB-A 3.0 ports, and a USB-C data port, each providing 5Gbps transfer speeds. It also includes a USB-C PD input port for charging up to 100W and dual SD and TF card slots, all in a compact design.
- Flawless 4K@60Hz Video with HDMI: Delivers exceptional clarity and smoothness with its 4K@60Hz HDMI port, making it ideal for high-definition presentations and entertainment. (Note: Only the HDMI port supports video projection; the USB-C port is for data transfer only.)
- Double Up on Efficiency: The two USB-A 3.0 ports and a USB-C port support a fast 5Gbps data rate, significantly boosting your transfer speeds and improving productivity.
- Fast and Reliable 85W Charging: Offers high-capacity, speedy charging for laptops up to 85W, so you spend less time tethered to an outlet and more time being productive.
- What You Get: Anker USB-C Hub (7-in-1), welcome guide, 18-month warranty, and our friendly customer service.
What is crawl budget, and how can sites avoid wasting it?
Google describes crawl budget as the set of URLs it can and wants to crawl. Crawl capacity concerns avoiding harm to the host; crawl demand varies with factors such as site size, update frequency, page quality, relevance, popularity, URL inventory, and how stale pages are. There is no single crawl rate or exact threshold that applies to every site. See Google’s crawl-budget guidance.
URL structure can create unnecessary work. Faceted navigation, sorting and filtering combinations, unrestricted calendars, session IDs, and malformed relative links can generate very large or effectively unbounded URL spaces. Google recommends consolidating duplicates, limiting redundant URL variants, maintaining current sitemaps, avoiding long redirect chains, and returning 404 or 410 for permanently removed pages. See the crawl-budget guide and Google’s URL-structure guidance.
- Use consistent canonical URL forms so equivalent pages do not multiply in the crawl queue.
- Keep internal links and sitemap entries pointed at preferred URLs rather than redirecting variants.
- Limit calendar and filter combinations when they do not provide distinct useful content.
- Return an accurate not-found or gone status for removed pages instead of serving an empty page as if it were valid.
Does a crawler need to run JavaScript?
Not always. A simple crawler can fetch HTML and parse links without launching a browser. That may miss content or links inserted only after client-side JavaScript runs. Google says its crawler renders pages and executes JavaScript, but a custom crawler only needs rendering when the target content is unavailable in the fetched HTML or the task depends on browser-rendered output. Browser rendering adds cost and complexity, so treat it as a requirement to verify, not a default. See Google’s JavaScript SEO basics.
For a quick visual inspection of a rendered page rather than building browser automation, ScreenshotNeo offers a screenshot API and MCP server. A screenshot is useful for checking rendered appearance, but it is not a substitute for a crawler that discovers, queues, and processes a site’s URLs.
Rank #4
- Dual Converters, Infinite Potential：Includes 2× USB C male to USB A female adapters and 2× USB A male to USB C female adapters. Perfect for a wide range of uses—tablets with Bluetooth keyboards, expand USB ports on macbook, and more. Two different converters for all your daily needs
- Next-Level 10Gbps & 3A Charging: No more slow 480Mbps, this usb to usb c adapter has a transfer speed of up to 10Gbps, allowing you to do more transferring in less time. This usb adapter fits both USB A and USB C charger, supporting up to 3A fast charging
- Upgraded Exquisite Craftsmanship: With an aluminum alloy housing and metal connector, the usbc to usb adapter is extremely durable and sturdy. Rigorously tested to withstand more than 10,000 times of plugging and unplugging, ensuring long-lasting performance
- Broad Compatible: The usb c to usb adapter widely supports all USB C/ USB A devices like laptops, tablets, cellphones, car chargers, and phone chargers. Such as compatible with MacBook Pro/Air 2023/2022, Thunderbolt 4/3 Devices,Apple MagSafe Watch 9/8/7/SE/Ultra, iPad Pro 2022/2021, Samsung Galaxy S23/S20/S10, and iPhone 17/16/15 Pro. Plug and play
- Please Note: To reach 10Gbps speed, keep the cable under 3.3 ft. For USB A Male to USB C adapters, try flipping the USB C connector. USB C Male to USB A adapters support bidirectional 10Gbps transfer within 3.3 ft
Or skip the browser setup
For a single visual capture, ScreenshotNeo takes a URL in one request and returns an image or PDF. See the ScreenshotNeo API documentation.
curl -G "https://api.screenshotneo.com/v1/shot" -d access_key=YOUR_API_KEY --data-urlencode url=https://stripe.com -o shot.webp- Cookie and consent banners, newsletter popups, and chat widgets are removed before the shot; each cleanup step can be turned off.
- Bot checks or CAPTCHAs, blank pages, timeouts, failed loads, and cache hits are not billed; response headers report page verdict and billing status.
- An MCP server provides
take_screenshot,get_page_info, andcapture_pdftools for AI agents and MCP clients. - The Free plan includes 1,000 screenshots per month with no card; paid plans start at $5 for 3,000.
Sign up for ScreenshotNeo’s free plan to get 1,000 screenshots a month with no card.
Troubleshooting a small crawl
The crawler keeps revisiting the same pages
Normalize URLs consistently and mark them as seen before adding them to the queue. Differences such as fragments, tracking parameters, trailing slashes, or query parameter order can create duplicate entries if your crawler treats each string as unique. Only remove query parameters when you know they do not identify distinct content.
The crawl grows without stopping
Set a page cap and explicit host or path boundary, then inspect which links are generating new URLs. Filters, sorting, session IDs, and calendar navigation can expand the URL space dramatically; restrict such patterns when they are outside your task.
Do these 3 things before closing this tab:
1Clear out junk files and repair common Windows errors2Fix the driver behind crashes, sound loss and screen glitches3Repair Windows errors before they cause bigger problemsBest Value
- 5-in-1 Connectivity: Equipped with a 4K HDMI port, a 5 Gbps USB-C data port, two 5 Gbps USB-A ports, and a USB C 100W PD-IN port. Note: The USB C 100W PD-IN port supports only charging and does not support data transfer devices such as headphones or speakers.
- Powerful Pass-Through Charging: Supports up to 85W pass-through charging so you can power up your laptop while you use the hub. Note: Pass-through charging requires a charger (not included). Note: To achieve full power for iPad, we recommend using a 45W wall charger.
- Transfer Files in Seconds: Move files to and from your laptop at speeds of up to 5 Gbps via the USB-C and USB-A data ports. Note: The USB C 5Gbps Data port does not support video output.
- HD Display: Connect to the HDMI port to stream or mirror content to an external monitor in resolutions of up to 4K@30Hz. Note: The USB-C ports do not support video output.
- What You Get: Anker 332 USB-C Hub (5-in-1), welcome guide, our worry-free 18-month warranty, and friendly customer service.
Important content is missing
Check whether the content exists in the fetched HTML. If it appears only after JavaScript runs, use a rendering approach for those pages; if it is absent even in a browser, the crawler cannot extract it from that response.
The target site slows down or returns server errors
Reduce concurrency, increase delays, and back off after errors such as HTTP 500. Do not respond to failures by immediately increasing request volume.
A robots.txt rule seems ineffective
Verify the file is at the top level of the correct host, protocol, and port, and that its directives match the crawler’s user agent and target path. Remember that robots.txt is not privacy protection and does not itself guarantee that a URL is absent from search results.
Frequently Asked Questions
Does crawling a page mean Google will index it?
No. Crawling, indexing, and serving results are separate stages; a fetched page may not be indexed or shown.
Free tools Windows power users keep installed
One-click scans. No signup required.
Does robots.txt block a page from Google Search?
It can discourage compliant crawling, but it is not a reliable way to hide a URL or protect private content.
Can I crawl a website without a browser?
Yes, if the HTML response contains the content and links your task needs. Browser rendering is needed only when client-side JavaScript supplies relevant content.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
