--- title: #basics description: 52 articles about basics — guides and explainers from the WatchFor team. canonical: https://watchfor.io/blog/tag/basics --- [All posts](/blog) # #basics Articles tagged "basics". [All](/blog)[Monitoring](/blog/category/monitoring)[Networking](/blog/category/networking)[Performance](/blog/category/performance)[Security](/blog/category/security)[Reliability](/blog/category/reliability)[Email](/blog/category/email)[DevOps](/blog/category/devops)[Engineering](/blog/category/engineering) [All articles](/blog/all) 52 article s · page 1 of 3 [MonitoringJul 30, 2026 ## Heartbeat & Cron Job Monitoring: the Dead Man's Switch Your Backups Deserve Most monitoring checks that something is up. Heartbeat monitoring does the opposite — it alerts when something that should run goes silent. The concept, who needs it, and how to set it up so a dead backup job can't hide for three weeks.WatchFor Team6 min read](/blog/heartbeat-cron-monitoring)[NetworkingJun 26, 2026 ## SSH explained: secure remote access, keys, and sessions SSH is how you securely log into and control machines anywhere in the world. Here's what it is, how password vs public-key auth really works, how to run remote commands, and the best clients for every OS.WatchFor Team5 min read](/blog/ssh-explained)[MonitoringJun 23, 2026 ## Uptime Monitoring 101: how to never be the last to know The worst way to find out your website is down is from an angry customer. This is the beginner-friendly guide to uptime monitoring — what it is, why it matters, and how to set it up so you always hear it first.WatchFor Team6 min read](/blog/uptime-monitoring-101)[NetworkingJun 22, 2026 ## HTTP Status Codes Explained: what 404, 500 and 503 really mean Every status code is your server trying to tell you something. Here's a plain-English guide to the ones you'll actually meet — what they mean, whose fault they are, and what to do about each.WatchFor Team4 min read](/blog/http-status-codes-explained)[NetworkingJun 12, 2026 ## How DNS Works (and What 'Propagation' Really Means) DNS is the internet's phonebook — and one of the most common causes of outages nobody understands. Here's how a domain name becomes an IP address, in plain English, plus what 'propagation' actually is.WatchFor Team4 min read](/blog/how-dns-works)[MonitoringJun 06, 2026 ## Synthetic vs Real User Monitoring (RUM): what's the difference? Synthetic monitoring and RUM answer two different questions about your site. Here's what each one does, where each shines, and why the best setups use both.WatchFor Team4 min read](/blog/synthetic-vs-real-user-monitoring)[MonitoringJun 03, 2026 ## API Monitoring Guide: how to watch the endpoints your business runs on Your website can be perfectly up while your API quietly fails — and APIs power the integrations, apps and partners you can't see. Here's how to monitor them properly.WatchFor Team4 min read](/blog/api-monitoring-guide)[MonitoringMay 30, 2026 ## What is 99.9% Uptime? The downtime hiding behind the nines “99.9% uptime” sounds almost perfect — until you do the maths. Here's exactly how much downtime each level of nines allows, how it's calculated, and how to pick a target you can actually hit.WatchFor Team3 min read](/blog/what-is-99-9-percent-uptime)[MonitoringMay 20, 2026 ## Observability vs Monitoring: what's the difference (and do you need both)? Monitoring tells you something broke. Observability helps you figure out why. Here's how the two differ, where each fits, and why modern teams lean on both.WatchFor Team3 min read](/blog/observability-vs-monitoring)[NetworkingMay 09, 2026 ## DNS Record Types Explained: A, AAAA, CNAME, MX, TXT and more Setting up a domain means meeting a zoo of record types — A, AAAA, CNAME, MX, TXT, NS. Here's what each one does, when to use it, and the gotchas that trip people up.WatchFor Team4 min read](/blog/dns-record-types-explained)[SecurityMay 06, 2026 ## How HTTPS Works: the TLS handshake, explained simply That little padlock does a lot of work. Here's what actually happens when you connect over HTTPS — the TLS handshake, certificates and encryption — without the cryptography headache.WatchFor Team3 min read](/blog/how-https-works)[NetworkingMay 02, 2026 ## Ping, Traceroute & MTR: network troubleshooting basics When something's slow or unreachable, three classic tools tell you whether it's you, the network, or them. Here's how ping, traceroute and MTR work — and when to reach for each.WatchFor Team3 min read](/blog/ping-traceroute-mtr)[PerformanceApr 22, 2026 ## Latency & Percentiles: why p99 matters more than the average Your average response time looks great — so why are users complaining? Because averages lie. Here's why percentiles like p95 and p99 tell the real story of how your service feels.WatchFor Team3 min read](/blog/latency-percentiles-p99)[PerformanceApr 08, 2026 ## What is a CDN? (And do you actually need one?) A CDN makes your site faster by serving it from locations close to your users. Here's how that works, what you actually gain, and whether your site needs one.WatchFor Team3 min read](/blog/what-is-a-cdn)[NetworkingApr 04, 2026 ## TCP vs UDP: the difference, explained simply Two protocols carry almost everything on the internet. TCP is the careful courier; UDP is the fast one that doesn't look back. Here's how they differ and when each is the right choice.WatchFor Team3 min read](/blog/tcp-vs-udp)[NetworkingMar 28, 2026 ## IPv4 vs IPv6: what's the difference (and why IPv6 exists)? Every device online needs an address — and we ran out of the old kind. Here's the difference between IPv4 and IPv6, why the switch is happening, and whether you need to care.WatchFor Team3 min read](/blog/ipv4-vs-ipv6)[PerformanceMar 14, 2026 ## What is TTFB (Time to First Byte) and how to improve it TTFB is the first number that tells you whether your backend is fast or slow. Here's what Time to First Byte measures, what's 'good', what makes it bad, and how to bring it down.WatchFor Team3 min read](/blog/ttfb-explained)[NetworkingMar 12, 2026 ## 404 Not Found: what it means and how to handle it 404 is the internet's most famous error — and unlike most, it's often nobody's emergency. Here's what it means, when it's fine, when it isn't, and how to handle it well.WatchFor Team3 min read](/blog/404-not-found)[NetworkingMar 10, 2026 ## 403 Forbidden: causes and how to fix it A 403 means the server understood you perfectly — and is refusing anyway. Here's what causes 'Forbidden', how it differs from 401, and how to track down the fix.WatchFor Team2 min read](/blog/403-forbidden)[NetworkingMar 08, 2026 ## 401 vs 403: Unauthorized vs Forbidden 401 and 403 are the two 'you can't have this' codes — and they're constantly confused. Here's the simple rule for telling them apart, with examples.WatchFor Team3 min read](/blog/401-vs-403) --- Canonical page: https://watchfor.io/blog/tag/basics · Site guide: https://watchfor.io/llms.txt