Tech Docs

Learn how electrical power moves through switchgear, switchboards, panelboards, PDUs, RPPs, and busway, how the equipment differs, and how to read a simple facility one-line safely.

Learn where to run net session, how to read incoming Windows file-sharing sessions, and how inspection differs from disconnection. Includes three videos, a diagram, and a read-only lab.

Learn how usermod changes a Linux account, why -aG preserves existing group memberships, and how to inspect, change, and verify account settings in a simple lab.

A context manager handles setup and cleanup around a block of Python code. The easiest example is a file. You open it, use it, and then it needs to be closed. Python’s with statement lets that cleanup happen automatically when the block ends. Start with the smallest useful example Read it in plain English: Open…

A Python lambda creates a small function from one expression. You already know how to create a normal function with def. A lambda is another way to create a function when the job is very small. Start with the normal function Output: This function takes one value, doubles it, and returns the result. Now write…

An iterator gives you one item at a time and remembers where it is. You already use iteration whenever you write a for loop. In this lesson, we look underneath the loop and see the simple tools Python uses: iter() and next(). Start with a normal list The list contains three names. We can ask…

A list comprehension is a short way to build a new Python list from another iterable. The easiest way to understand it is to start with a normal for loop and then shorten that same idea. Start with a normal loop Output: This code says: take each number, square it, and add the result to…

A network switch connects devices on a local network and forwards Ethernet frames between its ports. Think of a small office. A PC, printer, server, and Wi-Fi access point can all plug into the same Ethernet switch. The switch gives those wired devices a place to exchange local network traffic. Start with one simple picture…

A network interface is the part of a device that lets it connect to a network. You will often hear the term NIC, short for Network Interface Card or network interface controller. The everyday idea is simple: the NIC or network adapter is the computer’s connection point to Ethernet or Wi-Fi. It does not always…

Polymorphism means the same kind of call can produce different behavior depending on the actual object. In C++, a virtual function lets a derived class provide its own version of a base-class function and have that version selected through a base-class reference or pointer. Start with one simple idea: The smallest useful example Output: The…

Learn Python generators and yield with simple examples, next(), generator expressions, lazy iteration, and memory-efficient processing.

A float switch turns liquid level into a simple electrical ON/OFF signal. Picture the float inside a toilet tank or the float on a sump pump. As the water rises or falls, the float moves. In an electrical float switch, that movement changes an electrical contact. The basic chain is: The simplest example Imagine a…