VPN

A virtual private network (VPN) extends a private network across a public network and enables users to send and receive data across shared or public networks as if their computing devices were directly connected to the private network. Applications running on an end system (PC, smartphone etc.) across a VPN may therefore benefit from the functionality, security, and management of the private network. Encryption is a common, though not an inherent, part of a VPN connection.

VPNs can be characterized as host-to-network or remote access by connecting a single computer to a network or as site-to-site for connecting two networks.

menu bar

What’s in the menu bar on Mac?

The menu bar runs along the top of the screen on your Mac. Use the menus and icons in the menu bar to choose commands, perform tasks, and check status.

You can set an option in General preferences to automatically hide the menu bar; then it’s shown only when you move the pointer to the top of the screen.

Apple menu

The Apple menu , located in the top-left corner of the screen, contains commands for things you do frequently, such as update apps, open System Preferences, lock your screen, or shut down your Mac. See What’s in the Apple menu?

App menus

App menus are located next to the Apple menu. The name of the app you’re using appears in bold, followed by other menus, often with standard names such as File, Edit, Format, or Window. Each app has a Help menu to make it easy to get information about using an app. See Use the built-in help.

Each menu contains commands, many of which are available in most apps. For example, the Open command is often in the File menu. For information about the symbols in the menu commands, see What are those symbols shown in menus?

Status menus

Toward the right end of the menu bar are status menus, typically represented by icons. Use these menus to check the status of your Mac or quickly access features—for example, quickly turn Wi-Fi on or off or check your computer’s battery charge.

You can add status menus, such as the emoji viewer or a Volume control icon. You can also add status menus for some apps when you install them.

To rearrange the status menu icons, press and hold the Command key while dragging the items. To remove an icon, press and hold the Command key and drag the icon out of the menu bar.

Spotlight

Click the Spotlight icon , located after the status menus, to use Spotlight to search for items on your Mac and more.

Siri

Following Spotlight is the Siri icon —click it to ask Siri to do things like open files or apps, or to find things on your Mac or on the internet. You can easily keep Siri results handy on your desktop or in Notification Center.

Notification Center

At the right end of the menu bar, click the Notification Center icon  to use Notification Center to view details about your day and catch up on notifications you missed.

MBA

The MacBook Air (MBA) is a line of laptop computers developed and manufactured by Apple Inc. It consists of a full-size keyboard, a machinedaluminum case, and a thin light structure. The Air was originally positioned as a premium ultraportable positioned above the previous MacBook line.[2] Since then, the Air has become Apple's entry-level laptop due to the original MacBook's discontinuation in 2011, as well as lowered prices on subsequent iterations. In the current product line, the MacBook Air sits below the performance range MacBook Pro.

Identify your MacBook Air model

Meh

Meh (/mɛ/) is an interjection used as an expression of indifference or boredom. It is often regarded as a verbal equivalent of a shrug of the shoulders. The use of the term "meh" shows that the speaker is apathetic, uninterested, or indifferent to the question or subject at hand. It is occasionally used as an adjective, meaning something is mediocre or unremarkable.[1]

OUI

An organizationally unique identifier (OUI) is a 24-bit number that uniquely identifies a vendor, manufacturer, or other organization.

OUIs are purchased from the Institute of Electrical and Electronics Engineers (IEEE) Registration Authority by the assignee (IEEE term for the vendor, manufacturer, or other organization). They are used to uniquely identify a particular piece of equipment through derived identifiers such as MAC addresses,[1][2] Subnetwork Access Protocol protocol identifiers, World Wide Names for Fibre Channel devices.[3]

In MAC addresses, the OUI is combined with a 24-bit number (assigned by the assignee of the OUI) to form the address. The first three octets of the address are the OUI.

http://standards-oui.ieee.org/oui.txt

https://www.wireshark.org/tools/oui-lookup.html