LPI 010-160 Dumps for Linux Essentials - Exam 010, (version 1.6) Success in 2026

The operator that matches the preceding character either zero or one time in a regular expression is the question mark (?). This operator is also known as the optional quantifier, because it makes the preceding character or group of characters optional. For example, the regular expression colou?r matches both color and colour, because the u is optional. The question mark can also be used to modify other quantifiers, such as * (zero or more), + (one or more), or {m,n} (between m and n times), to make them non-greedy, meaning they will match the shortest possible string instead of the longest. For example, the regular expression .*? matches any character zero or more times, but as few as possible. The question mark is one of the basic regular expression operators covered in the Linux Essentials certification program from the Linux Professional Institute (LPI).Reference:

Linux Essentials - Linux Professional Institute (LPI)

Regular Expressions:Difference between 'optional occurrence' and 'zero ...

A Linux distribution is a collection of software that is based on the Linux kernel and can be installed on a computer or a device to create a functional operating system. A Linux distribution typically includes the Linux kernel, a set of system utilities and libraries, a graphical user interface (GUI), a package manager, and various applications and services. A Linux distribution may also include additional software or features that are specific to the distribution's goals, target audience, or philosophy. For example, some Linux distributions are designed for desktop users, while others are optimized for servers, embedded systems, or security. Some Linux distributions are based on other Linux distributions, while others are developed independently. Some Linux distributions are free and open source, while others are proprietary or commercial. Some Linux distributions are popular and widely used, while others are niche or experimental. Some examples of Linux distributions are Ubuntu, Fedora, Debian, Mint, Arch, and Red Hat.Reference:

Linux Essentials Topic 101: System Architecture, section 101.1: Determine and configure hardware settings.

Linux Essentials Topic 102: Linux Installation and Package Management, section 102.1: Design hard disk layout.

Linux Essentials Topic 103: GNU and Unix Commands, section 103.1: Work on the command line.

Linux Essentials Topic 104: The Linux Operating System, section 104.1: Boot the system.

Linux Essentials Topic 105: The Power of the Command Line, section 105.1: Use text streams and filters.

Linux Essentials Topic 106: Security and File Permissions, section 106.3: Modify file and directory permissions.

What is a Linux distribution? - Linux.com

Linux distribution - Wikipedia

Best Linux Distributions For Everyone in 2023 - It's FOSS

CentOS is a Linux distribution that is based on the source code of Red Hat Enterprise Linux (RHEL). It is a free and open-source community-supported OS that provides an enterprise-level computing platform. CentOS is fully compatible with RHEL and can run the same applications and packages. Therefore, CentOS allows the team members to apply as much of their Red Hat Enterprise Linux knowledge as possible for their hobby project.Reference:

Linux Essentials Version 1.6 Objectives1, Topic 1.1: Linux Evolution and Popular Operating Systems, Subtopic: Linux Distributions

Linux Essentials Version 1.6 Exam Preparation Guide2, Section 1.1: Linux Evolution and Popular Operating Systems, Page 7

CentOS Website3, About CentOS Linux

Red Hat Enterprise Linux derivatives - Wikipedia4

The files /etc/passwd and /etc/group are the source of the information in the following output:

uid=1000 (bob) gid=1000 (bob) groups=1000 (bob), 10 (wheel), 150 (docker), 1001 (libvirt) (wireshark), 989

The /etc/passwd file contains information about user accounts, such as the username, password, user ID (UID), group ID (GID), full name, home directory, and login shell1.The /etc/group file contains information about groups, such as the group name, password, group ID (GID), and members2.

The output shows the UID, GID, and group membership of the user bob. The UID and GID of bob are 1000, which can be found in the /etc/passwd file. The groups that bob belongs to are bob, wheel, docker, libvirt, wireshark, and 989, which can be found in the /etc/group file. The group names are shown in parentheses after the GID, except for the last group, which has no name.

The other options are not files that store user and group information in Linux. The /etc/id file does not exist by default. The /home/index file is not a standard file and has no relation to user and group information. The /var/db/users file is not a standard file and has no relation to user and group information.Reference:

Linux Essentials Exam Objectives, Version 1.6, Topic 103.1, Weight 2

Linux Essentials Certification Guide, Chapter 3, Page 51-52

Linux Filesystem Hierarchy, Chapter 3, Page 17-18

Linux Users and Groups, Chapter 2, Page 9-10

Linux passwords are not stored in plain text, but in a scrambled or encrypted form known as a hash. A hash is a one-way function that transforms a string of characters into a fixed-length value. The same input always produces the same hash, but it is impossible to reverse the process and recover the original input from the hash. This way, the system can verify the user's password without exposing it to anyone who can read the file where the hashes are stored. The file that contains the password hashes is /etc/shadow, which is only readable by the root user or members of the shadow group. The passwd utility is used to change the user's password, which updates the hash in the /etc/shadow file.Reference:Linux Essentials 1.6 Topic 105: Security and File Permissions,How to Change Account Passwords on Linux,Where is my password stored on Linux?