AppArmor locks down programs on your Ubuntu system, allowing them only the permissions they require in normal use – particularly useful for server software that may become compromised. AppArmor includes simple tools you can use to lock down other applications.
AppArmor is an important security feature that’s been included by default with Ubuntu since Ubuntu 7.10. However, it runs silently in the background, so you may not be aware of what it is and what it’s doing.
Ubuntu and Linux Mint come with a “Guest Session” account, which anyone can log into from the login screen – no password required. If you’d rather restrict access to your computer, you can disable the guest account.
One of the defining features of Linux and other UNIX-like operating systems is that “everything is a file.” This is an oversimplification, but understanding what it means will help you understand how Linux works.
Ubuntu’s Update Manager keeps your packages at the latest version, but occasionally a new package version may not work properly. You can downgrade an installed package and lock it at a specific version to prevent it from being updated.
Linux logs a large amount of events to the disk, where they’re mostly stored in the /var/log directory in plain text. Most log entries go through the system logging daemon, syslogd, and are written to the system log.
There are several ways to change your default applications on Ubuntu. Whether you’re changing the default application for a particular task, file type, or a system-level application like your default text editor, there’s a different place to go.
If you’re using Linux, you don’t need VirtualBox or VMware to create virtual machines. You can use KVM – the kernel-based virtual machine – to run both Windows and Linux in virtual machines.
Installing software on Linux involves package managers and software repositories, not downloading and running .exe files from websites like on Windows. If you’re new to Linux, this can seem like a dramatic culture shift.
The Nautilus file manager included with Ubuntu includes some useful features you may not notice unless you go looking for them. You can create saved searches, mount remote file systems, use tabs in your file manager, and more.
If you’re coming from Windows, the Linux file system structure can seem particularly alien. The C:\ drive and drive letters are gone, replaced by a / and cryptic-sounding directories, most of which have three letter names.
People often “tether” their computers to their smartphones, sending their computer’s network traffic over the device’s cellular data connection. “Reverse tethering” is the opposite – tethering your Android smartphone or tablet to your PC to use your PC’s Internet connection.
Ubuntu One, Ubuntu’s built-in cloud file storage service, allows you to make files publically available online or share them privately with others. You can share files over the Internet right from Ubuntu’s file browser.
Like CCleaner on Windows, BleachBit frees space by deleting unimportant files and helps maintain your privacy by deleting sensitive data. And, just like CCleaner, there’s more you can do with BleachBit than just clicking a single button.
Use Nautilus-Actions to easily and graphically create custom context menu options for Ubuntu’s Nautilus file manager. If you don’t want to create your own, you can install Nautilus-Actions-Extra to get a package of particularly useful user-created tools.
Like most things on Linux, the sudo command is very configurable. You can have sudo run specific commands without asking for a password, restrict specific users to only approved commands, log commands run with sudo, and more.
Ubuntu doesn’t use a separate /home partition by default, although many Linux users prefer one. Using a separate home partition allows you to reinstall Ubuntu without losing your personal files and settings.
Some Android apps on Google Play claim to be incompatible with various devices. There’s a good chance that these apps will run fine on many of these devices – you can bypass this check with root access.
If you have a single wired Internet connection – say, in a hotel room – you can create an ad-hoc wireless network with Ubuntu and share the Internet connection among multiple devices. Ubuntu includes an easy, graphical setup tool.
You’ve probably noticed that Ubuntu comes with a Public folder in your home directory. This folder isn’t shared by default, but you can easily set up several different types of file-sharing to easily share files on your local network.
Access an encrypted home directory when you’re not logged in – say, from a live CD – and all you’ll see is a README file. You’ll need a terminal command to recover your encrypted files.
Is your desktop so cluttered you can’t find anything? Is your Start menu so long you have to scroll to see what programs are there? If so, you probably need an application launcher to organize your desktop and make your life easier.
Ubuntu offers to encrypt your home directory during installation. The encryption has some drawbacks – there’s a performance penalty and recovering your files is more difficult. If you change your mind later, you can remove the encryption without reinstalling Ubuntu.
Ubuntu offers to encrypt your home folder during installation. If you decline the encryption and change your mind later, you don’t have to reinstall Ubuntu. You can activate the encryption with a few terminal commands.
Ubuntu can quickly encrypt USB flash drives and external hard drives. You’ll be prompted for your passphrase each time you connect the drive to your computer – your private data will be secure, even if you misplace the drive.