Mac os x -
Apple Inc.'s Macintosh OS X (pronounced "OS Ten") is the operating system distributed with Apple computers. It includes heavily used several programs by default, including Apple Mail, a web browser called Safari, and an Apple Address Book, and iCal.
EFI boot
The firmware is responsible for initializing the hardware and performing a POST (Power-On Self Test).
The default boot volume is stored in NVRAM and can be configured through the "Startup Disk" preference pane or the nvram command line utility. E.g. to print all of the firmware variables.
nvram -p 
Additional boot arguments can be provided via the "boot-args" value 2.
Mac OS X extends EFI with a read-only HFS+ driver. According to 3 HFS+ volume header fields are used to point to a "blessed file" to be loaded as an EFI application. Though it is not clear which header field the source is referring to but likely related to the "bless" utility
The firmware starts the Mac OS X boot loader (boot.efi). The bootloader displays a dark grey Apple logo on the screen and loads the Darwin kernel from disk, as well as the essential driver extensions.
The bootloader can be eithe a MZ-PE/COFF or EFI fat binary type executables and is commonly stored in:
/com.apple.recovery.boot/boot.efi /System/Library/CoreServices/boot.efi /usr/standalone/i386/boot.efi 
The behavior of the bootloader can be configured in the com.apple.Boot.plist which can be found in:
/Library/Preferences/SystemConfiguration/ 
Disk image types
Mac OS X has support for various disk image types built-in, some of which are:
read-write disk image (.dmg), which can be stored in Raw Image Format or Universal Disk Image Format (udif)
Sparse disk image (.spareimage)
Sparse bundle disk image (.sparsebundle)
Burn Folder
Mac OS X Burn Folder:
$NAME.fpbf 
This folder normally contains alias files (similar to LNK files under Windows). Which should have the following signature.
00000000 62 6f 6f 6b 00 00 00 00 6d 61 72 6b 00 00 00 00 |book....mark....| 
These alias files contain additional date and time values.
Also check the following files for references to deleted .fpbf paths:
/Users/$USERNAME/Library/Preferences/com.apple.finder.plist /Users/$USERNAME/Library/Preferences/com.apple.sidebarlists.plist 
Actual burning of optical media is logged in:
/var/log/system.log /Users/$USERNAME/Library/Logs/DiscRecording.log /private/var/.logs_exporter/cache/Users/$USERNAME/Library/Logs/DiscRecording.log 
Launch Agents
System-wide:
/Library/LaunchAgents /System/Library/LaunchAgents 
Per user:
/Users/$USERNAME/Library/LaunchAgents 
These directories contain Property list (plist) files.
Launch Daemons
System-wide:
/Library/LaunchDaemons /System/Library/LaunchDaemons 
These directories contain Property list (plist) files.
Startup Items
/Library/StartupItems/ /System/Library/StartupItems/ 
Crash Reporter
/Library/Application Support/CrashReporter 
Contains text files named .crash, .diag, .spin
Diagnostic Reports
/Library/Logs/DiagnosticReports 
Internet Plug-Ins
System-wide:
/Library/Internet Plug-Ins 
Per user:
/Users/$USERNAME/Library/Internet Plug-Ins 
Quarantine event database
See 6
Snow Leopard and earlier
/Users/$USER/Library/Preferences/com.apple.LaunchServices.QuarantineEvents SELECT datetime(LSQuarantineTimeStamp + 978307200, "unixepoch") as LSQuarantineTimeStamp, LSQuarantineAgentName, LSQuarantineOriginURLString, LSQuarantineDataURLString from LSQuarantineEvent; 
Lion and later
/Users/$USER/Library/Preferences/com.apple.LaunchServices.QuarantineEventsV2 
sleepimage
This file is similar to the hibernation file on Windows.
/private/var/vm/sleepimage 
Also see: 7
Last shutdown logs
/private/var/log/com.apple.launchd/launchd-shutdown.system.log /private/var/log/com.apple.launchd/launchd-shutdown.system.log.1 
Package Files (.PKG)
Package Files (.PKG) are XAR archives that contain a cpio archive and metadata 9.
Encodings / Codepages
Mac OS X typically uses UTF-16 big-endian to store Unicode strings, it also defines several codepages 10 that can be used to store ASCII strings.
Note that some of these codepages can differ for different versions of Mac OS.
Codepage Identifier Description 
0	MacRoman	Encoding used for English and several other Western languages, also see: Wikipedia: Mac OS Roman,Unicode.org: ROMAN.TXT (sometimes referred to as Microsoft codepage 10000 though it is unclear if this is the pre Mac OS 8.5 MacRoman variant)	
1	MacJapanese	also see: Unicode.org: JAPANESE.TXT (sometimes referred to as Mac Shift Jis or Microsoft codepage 10001)	
2	MacChineseTrad	also see: Unicode.org: CHINTRAD.TXT (sometimes referred to as Mac Big5 or Microsoft codepage 10002)	
3	MacKorean	also see: Unicode.org: KOREAN.TXT (sometimes referred to as Mac Hangul or Microsoft codepage 10003)	
4	MacArabic	Encoding used for Arabic texts, also see: Wikipedia: MacArabic encoding, Unicode.org: ARABIC.TXT (sometimes referred to as Microsoft codepage 10004). Note that certain Unicode characters can be translated into multiple codepage characters such as U+0020 can be represented as 0x20 or 0xa0.	
5	MacHebrew	also see: Unicode.org: HEBREW.TXT (sometimes referred to as Microsoft codepage 10005)	
6	MacGreek	Encoding used for Greek scripts, Wikipedia: MacGreek encoding, Unicode.org: GREEK.TXT (sometimes referred to as Microsoft codepage 10006)	
7	MacCyrillic	Encoding used for Cyrillic scripts, also see: Wikipedia: Mac OS Cyrillic encoding, Unicode.org: CYRILLIC.TXT. Note that MacCyrillic supersedes the MacCyrillic encoding prior to Mac OS 9.0 (sometimes referred to as MacCyrillicCurrSignStdVariant, MacRussian or Microsoft codepage 10007) and MacUkrainian, Unicode.org: UKRAINE.TXT (sometimes referred to as MacCyrillicCurrSignUkrVariant or Microsoft codepage 10017).	
9	MacDevanagari	also see: Unicode.org: DEVANAGA.TXT	
10	MacGurmukhi	also see: Unicode.org: GURMUKHI.TXT	
11	MacGujarati	also see: Unicode.org: GUJARATI.TXT	
12	MacOriya		
13	MacBengali		
14	MacTamil		
15	MacTelugu		
16	MacKannada		
17	MacMalayalam		
18	MacSinhalese		
19	MacBurmese		
20	MacKhmer		
21	MacThai	also see: Wikipedia: ISO/IEC 8859-11 - Mac OS Thai, Unicode.org: THAI.TXT (sometimes referred to as Microsoft codepage 10021)	
22	MacLaotian		
23	MacGeorgian		
24	MacArmenian		
25	MacChineseSimp	also see: Unicode.org: CHINSIMP.TXT (sometimes referred to as Mac GB2312 or Microsoft codepage 10008)	
26	MacTibetan		
27	MacMongolian		
28	MacEthiopic		
29	MacCentralEurRoman	Encoding used for languages that use the Latin script, such as Central European and Southeastern European languages, also see: Wikipedia: Mac OS Central European encoding, Unicode.org: CENTEURO.TXT (sometimes referred to as Mac East Europe or Microsoft codepage 10029)	
30	MacVietnamese		
31	MacExtArabic		
33	MacSymbol	also see: Unicode.org: SYMBOL.TXT	
34	MacDingbats	also see: Wikipedia: Zapf Dingbats, Unicode.org: DINGBATS.TXT	
35	MacTurkish	also see: Wikipedia: Mac OS Turkish encoding, Unicode.org: TURKISH.TXT (sometimes referred to as Microsoft codepage 10081)	
36	MacCroatian	also see: Wikipedia: Mac OS Croatian encoding,Unicode.org: CROATIAN.TXT (sometimes referred to as Microsoft codepage 10082)	
37	MacIcelandic	also see: Wikipedia: Mac OS Icelandic encoding, Unicode.org: ICELAND.TXT (sometimes referred to as Microsoft codepage 10079)	
38	MacRomanian	also see: Wikipedia: Mac OS Romanian encoding,Unicode.org: ROMANIAN.TXT (sometimes referred to as Microsoft codepage 10010)	
39	MacCeltic	also see: Unicode.org: CELTIC.TXT	
40	MacGaelic	also see: Unicode.org: GAELIC.TXT	
140	MacFarsi	also see: Wikipedia: MacFarsi encoding, Unicode.org: FARSI.TXT	
152	MacUkrainian	see: MacCyrillic	
236	MacInuit	also see: Unicode.org: INUIT.TXT	
252	MacVT100		
255	MacHFS		
2564	MacRomanLatin1		
Also see
MacOS Process Monitoring
Acquiring a MacOS System with Target Disk Mode
Converting Binary Plists
FileVault Disk Encryption
File Vault
Formats
Apple File System (apfs)
Apple Partition Map (apm)
Basic Security Module (BSM) file format
DMG
Hierarchical File System Plus (HFS+) format
Property list (plist)
External Links
Wikipedia entry on OS X
Inside Macintosh, by Apple Computer, Inc., 1993
Command Line ALF on Mac OS X
mac-security-tips
Hidden backdoor API to root privileges in Apple OS X, by Emil Kvarnhammar, April 9, 2015
Max OS X Internals book (1st ed) by Jonathan Levin
The Boot Loader, by Apple
EFI
The Intel Mac boot process, by the rEFIt project - Carving up EFI fat binaries, by snare, February 24, 2012
iCloud
iCloud: iCloud security and privacy overview
Background and login items
Apple's BookmarkData - exposed!, by Michael Lynn, October 24, 2015
Block Blocking Login Items - parsing apple's login item files to detect persistence, by Objective See, July 23, 2018
Mac Alias Format, by mac-alias project
Mac Bookmark Format, by mac-alias project
ColorSync
Technical Note TN2035 - ColorSync on Mac OS X
Internet Archive: Managing Color With ColorSync
ICC.1:2004-10 - Image technology colour management - Architecture, profile format, and data structure, by International Color Consortium (ICC)
ICC Profile Format Specification, by International Color Consortium (ICC), November 20, 1995
ICC profiles
ICC_Profile Tags
Adobe XMP Developer Center
Device Management Profile
LoginWindow
LoginWindowScripts
Finder Alias and Bookmark
Apple's BookmarkData - exposed!, by Michael Lynn, October 24, 2015
Bookmarks, a type of Alias: their access and use
Explainer: Links, Aliases and Bookmarks
Quarantine event database
Quarantine event database
NSKeyedArchiver
NSKeyedArchiver - An encoder that stores an object’s data to an archive referenced by keys
NSKeyedArchiver files – what are they, and how can I use them?, by Alex Caithness, April 4, 2012
Manual Analysis of ‘NSKeyedArchiver’ Formatted Plist Files - A Review of the NEW OS X 10.11 "Recent Items", January 01, 2016
How NSCoding and NSKeyedArchiver/Unarchiver Work Together to Encode/Decode Object, by Mark van Wijnen, August 16, 2022
Unified logging
New macOS Sierra (10.12) Forensic Artifacts – Introducing Unified Logging, by Sarah Edwards, November 13, 2016
Reviewing macOS Unified Logs, by Alexander Holcomb, August 31, 2022
Yet Another Assembler (YAA)
YAA: An Obscure MacOS Compressed File Format, by nightwatchcyber, June 14, 2020