Boss Guitar Effects Pedals

When Roland decided to form a subsidiary company dedicated to guitars in the early 1970s, they originally intended to call it MEG (Musical Engineering Group). Realizing, however, that Meg was a girl's name and believing this might dissuade male guitarists, they searched for a name that would connote power and mastership, and eventually came up with Boss.
The earliest Boss product was called B-100 The Boss, released in 1976. This came with a clip-on pre-amp and a pickup to amplify acoustic guitars. At this point the Boss company had not been formed and it was still technically a Roland product.
The first proper Boss foot pedal effect, in 1976, was called the CE-1 Chorus Ensemble, believed by many guitarists to be the "Holy Grail" of pedal chorus effects. It was a fairly large, AC-powered unit. It was popular with artists at the time such as Andy Summers and can be heard on various recordings.

Boss's line of compact pedals began in 1977 with the release of three pedals: an overdrive pedal (OD-1), a phaser pedal (PH-1) and a parametric equalizer called the Spectrum (SP-1). The Boss DS-1 was released the next year, in 1978. Also released in this year is the T Wah (TW-1) pedal. Their first compact chorus pedal (CE-2) came the next year (1979), and their first flanger pedal (BF-2) in 1980. In 1983 Boss released the DD-2 Digital Delay, the first mass-produced digital delay in a compact pedal format. In 1987 Boss released nine new pedals, including the Turbo Distortion (DS-2). The Metal Zone (MT-2) was released in 1991. The Heavy Metal (HM-2) distortion pedal was an integral part of the guitar sound of many styles of heavy metal music ever since. The pedals all share the same 'footprint', for compatibility with pedal boards.
Boss introduced COSM (Composite Object Sound Modeling), Roland's proprietary version of digital modeling technology, into their AC-3 Acoustic Simulator pedal in 2006. Boss has since released several pedals using COSM, including the FBM-1 '59 Fender Bassman pedal and FDR-1 '65 Fender Deluxe Reverb pedal, introduced at the Winter NAMM show in January 2007.
All Boss compact pedals use a "buffered bypass" type of silent foot switching utilizing Field Effect Transistors (FETs) to avoid clicks and pops. While not "true" bypass, the buffered bypass has the advantage of preventing signal loss due to long runs of cable, while keeping original guitar tone intact.

Overdrive/distortion
BD-2 Blues Driver (Used by Billie Joe Armstrong)
DB-5 Driver
DS-1 Distortion (Used by Dave Navarro and Kurt Cobain)
DS-2 Turbo Distortion (John Frusciante and Kurt Cobain)
MD-2 Mega Distortion (Used by Mick Thomson) during "Iowa" only.*
DF-2 Super Feedbacker and Distortion
OS-2 OverDrive/Distortion
OD-3 OverDrive
OD-2 Turbo Overdrive
OD-1 OverDrive
OD-2r Turbo Overdrive
SD-1 Super OverDrive
SD-2 Dual OverDrive
ST-2 Power Stack (2010) "Stack amp in a stomp box."
PW-2 Power Driver
XT-2 Xtortion
FZ-5 Fuzz
FZ-3 Fuzz
FZ-2 Hyper Fuzz (Used by Fieldy)
HM-2 Heavy Metal
HM-3 Hyper Metal
MZ-2 Digital Metalizer
ML-2 Metal Core
MT-2 Metal Zone
DN-2 Dyna Drive
FBM-1 Fender '59 - amplifier simulation of 1959 Fender Bassman
FDR-1 Fender '65 Deluxe - amplifier simulation of 1965 Fender Deluxe Reverb

Modulation
CE-1 Chorus Ensemble (used by John Frusciante)
CE-2 Chorus
CE-3 Chorus
CE-5 Chorus Ensemble (used digital components after 2001)
CH-1 Super Chorus (used digital components after 2001)
PH-1 Phaser
PH-1r Phaser
PH-2 Super Phaser
PH-3 Phase Shifter
VB-2 Vibrato
TR-2 Tremolo
PN-2 Tremolo/Pan
BF-2 Flanger (Used by Jason Newsted)
BF-3 Flanger
HF-2 Hi-Band Flanger
DC-2 Dimension C
DC-3 Digital Dimension a.k.a. "Digital Space D" later labeled.

Reverb/delay
RV-2 Digital Reverb
RV-3 Digital Reverb/Delay, with delay times up to 2,000ms. Used by Jonny Greenwood, Jonny Buckland, and Wes Borland
RV-5 Digital Reverb
RRV-10 Digital Reverb
FRV-1 Fender Reverb - amplifier simulation of 1963 Fender Spring Reverb
DSD-2 Digital Sampler/Delay
DSD-3 Digital Sampler/Delay
DM-1 Delay Machine
DM-2 Analog Delay
DM-3 Analog Delay
DD-2 Digital Delay (used by Tom Morello)
DD-3 Digital Delay
DD-5 Digital Delay
DD-6 Digital Delay - stereo pedal with longer delay times than DD-3
DD-7 Digital Delay
DD-20 Digital Delay

EQ/tonality
TW-1 T Wah
TW-1 Touch Wah
AW-2 Auto Wah
AW-3 Dynamic Wah
FT-2 Dynamic Filter
GE-6 Equalizer
GE-7 Equalizer
PQ-4 Parametric Equalizer
SP-1 Spectrum
AC-3 Acoustic Simulator
AC-2 Acoustic Simulator
CS-1 Compression Sustainer
CS-2 Compression Sustainer
CS-3 Compression Sustainer
EH-2 Enhancer

Pitch shift
PS-2 Digital Pitch Shifter/Delay
PS-3 Digital Pitch Shifter/Delay
PS-5 Super Shifter
PS-6 Harmonist (2010)
OC-2 Octaver a.k.a. "Octave" later labeled.
OC-3 Super Octave
HR-2 Harmonist

Other
LM-2 Limiter
LS-2 Line Selector
NF-1 Noise Gate
NS-2 Noise Suppressor
PSM-5 Power Supply and Master Switch
RC-2 Loop Station
RC-20XL Loop Station
RC-50 Loop Station
SG-1 Slow Gear
TU-2 Chromatic Tuner
TU-3 Chromatic Tuner (2010)
TU-1000 Chromatic tuner

Twin pedals for electric guitar

OD-20 Drive Zone
CE-20 Chorus Ensemble
EQ-20 Advanced EQ
DD-20 Giga Delay
RC-20XL Loop Station
RT-20 Rotary Ensemble
RE-20 Space Echo
SL-20 Slicer
WP-20G Wave Processor
OC-20G Poly Octave
GP-20 Amp Factory
VE-20 Voice Performer (2010)

Compact pedals for bass guitar

BF-2B Bass Flanger
CE-2B Bass Chorus
GE-7B Bass Equalizer
LM-2B Bass Limiter
PQ-3B Parametric Equalizer
ODB-3 Bass Overdrive
CEB-3 Bass Chorus
GEB-7 Bass Equalizer
LMB-3 Bass Limiter Enhancer
SYB-3 Bass Synthesizer
SYB-5 Bass Synthesizer

Drum machines

Boss Doctor Rhythm DR-55 (analog)
Boss Doctor Rhythm DR-110 (analog)
Boss Doctor Rhythm DR-220 A/E (12bit)
Boss Doctor Rhythm DR-3
Boss Doctor Rhythm DR-5
Boss Doctor Rhythm DR-550 mkI/mkII
Boss Doctor Rhythm DR-660
Boss Doctor Rhythm DR-670
Boss Doctor Rhythm DR-770
Boss Doctor Rhythm DR-880

Multi-effects processors

GT-3
GT-5
GT-6 & GT-6B Guitar Effects Processor
GT-8 Guitar Effects Processor
GS-10 Guitar and Bass Effects Processor for Studio
GT-10 & GT-10B Guitar/Bass Effects Processor
GT-PRO Guitar Effects Processor (rack-mounted)
ME-5 Guitar Effects Processor
ME-8 Guitar Effects Processor
ME-8B Bass Guitar Effects Processor
ME-10 Guitar Effects Processor
ME-20 & ME-20B - Guitar and Bass Multiple Effects
ME-25 Guitar Multiple Effects (2010)
ME-30 & ME-30B - Guitar and Bass Multiple Effects
ME-33 Guitar Multiple Effects
ME-50 & ME-50B - Guitar and Bass Multiple Effects
ME-70 - Guitar Multiple Effects
RC-50 Loop Station
BE-5- 5 Special Selected Effects for Guitarists (Chorus, Noise Suppressor, Digital Delay, Overdrive/Distortion, Compressor)
BE-5B- 5 Special Selected Effects for Bassists

Digital studios

Boss Micro BR 4 track
Boss BR 532 4 track
Boss BR 600 8 track
Boss BR 800 8 track
Boss BR 864 8 track
Boss BR 900CD 8 track
Boss BR 1200CD 12 track
Boss BR 1600CD 16 track