Milestone-Proposal:Introduction of the Apple Macintosh Computer, 1984

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Docket #:2014-06

This Proposal has been approved, and is now a Milestone


To the proposer’s knowledge, is this achievement subject to litigation? No

Is the achievement you are proposing more than 25 years old? Yes

Is the achievement you are proposing within IEEE’s designated fields as defined by IEEE Bylaw I-104.11, namely: Engineering, Computer Sciences and Information Technology, Physical Sciences, Biological and Medical Sciences, Mathematics, Technical Communications, Education, Management, and Law and Policy. Yes

Did the achievement provide a meaningful benefit for humanity? Yes

Was it of at least regional importance? Yes

Has an IEEE Organizational Unit agreed to pay for the milestone plaque(s)? Yes

Has an IEEE Organizational Unit agreed to arrange the dedication ceremony? Yes

Has the IEEE Section in which the milestone is located agreed to take responsibility for the plaque after it is dedicated? Yes

Has the owner of the site agreed to have it designated as an IEEE Milestone? Yes


Year or range of years in which the achievement occurred:

1984

Title of the proposed milestone:

Introduction of the Apple Macintosh Computer, 1984

Plaque citation summarizing the achievement and its significance:

The Apple Macintosh created a personal computing epoch with its complete graphical user interface (GUI) platform in a compact, portable, low-cost package featuring high-resolution bitmap graphics, one-button mouse, and innovative switching power supply. Influenced by the Lisa computer, its read-only memory (ROM)-based QuickDraw software provided a standard GUI platform empowering third-party developers to create revolutions in diverse areas, including desktop publishing and media editing.

200-250 word abstract describing the significance of the technical achievement being proposed, the person(s) involved, historical context, humanitarian and social impact, as well as any possible controversies the advocate might need to review.


IEEE technical societies and technical councils within whose fields of interest the Milestone proposal resides.


In what IEEE section(s) does it reside?

Santa Clara Valley

IEEE Organizational Unit(s) which have agreed to sponsor the Milestone:

IEEE Organizational Unit(s) paying for milestone plaque(s):

Unit: Santa Clara Valley Section
Senior Officer Name: Ed Aoki

IEEE Organizational Unit(s) arranging the dedication ceremony:

Unit: Santa Clara Valley Section
Senior Officer Name: Ed Aoki

IEEE section(s) monitoring the plaque(s):

IEEE Section: Santa Clara Valley Section
IEEE Section Chair name: Ed Aoki

Milestone proposer(s):

Proposer name: Brian A. Berg
Proposer email: Proposer's email masked to public

Please note: your email address and contact information will be masked on the website for privacy reasons. Only IEEE History Center Staff will be able to view the email address.

Street address(es) and GPS coordinates in decimal form of the intended milestone plaque site(s):

In the vicinity of the main entrance or the main lobby of the headquarters of Apple, Inc., at 1 Infinite Loop, Cupertino, CA 95014 (37.33182°N 122.03118°W) or at the new Apple Campus 2 (the "Spaceship") that is currently under construction in Cupertino, CA.

Describe briefly the intended site(s) of the milestone plaque(s). The intended site(s) must have a direct connection with the achievement (e.g. where developed, invented, tested, demonstrated, installed, or operated, etc.). A museum where a device or example of the technology is displayed, or the university where the inventor studied, are not, in themselves, sufficient connection for a milestone plaque.

Please give the address(es) of the plaque site(s) (GPS coordinates if you have them). Also please give the details of the mounting, i.e. on the outside of the building, in the ground floor entrance hall, on a plinth on the grounds, etc. If visitors to the plaque site will need to go through security, or make an appointment, please give the contact information visitors will need. The current headquarters of Apple, Inc., is a high profile location in Silicon Valley. It has a direct lineage to the work done by Steve Jobs and the Apple team that worked on the Macintosh. It is a location that is seen by and visited by thousands of visitors, vendors and Apple employees on a daily basis. There are not any other historical markers already on the site.

Are the original buildings extant?

The Macintosh team worked in many buildings that are in close vicinity to the current headquarters of Apple, Inc., at 1 Infinite Loop, Cupertino, CA 95014, which is a set of buildings first occupied in 1993.

Details of the plaque mounting:

TBD, but in the vicinity of the main entrance or the main lobby of the headquarters of Apple, Inc., at 1 Infinite Loop, Cupertino, CA 95014.

How is the site protected/secured, and in what ways is it accessible to the public?

The main entrance and the main lobby of the headquarters of Apple, Inc., at 1 Infinite Loop, Cupertino, CA 95014, are fully accessible to the public.

Who is the present owner of the site(s)?

Apple, Inc., owns all of the buildings at its headquarters.

What is the historical significance of the work (its technological, scientific, or social importance)? If personal names are included in citation, include justification here. (see section 6 of Milestone Guidelines)

The Apple Macintosh was the first widely successful personal computer offering an integrated standard graphical user interface (GUI). The Macintosh project was originally founded and named by Jef Raskin, who saw a need for a radically simplified GUI-based computer as a major step beyond the Apple II, and who hired the original engineering and marketing leaders. Steve Jobs later took over the project, and led it through and beyond the product’s introduction and roll-out in January 1984.

Some of the Apple II design features used in the Macintosh were (1) the video bitmap buffer being stored directly in system RAM, (2) the RAM refresh being automatically maintained as a result of reading the video bitmap buffer and painting it to the screen, (3) the use of an integrated switching power supply, and (4) the use of passive cooling to ensure quiet operation. The Macintosh included an internal high-resolution black & white bitmap display, floppy disk drive, external keyboard, mouse [Ref-1: '652 patent], speaker and integrated communications including a breakthrough low-cost local area network (LAN) known as AppleTalk (later LocalTalk).

The Macintosh was the first large-scale (and keystone) commercial user of the Sony 3.5” micro-floppy, a drive whose hard shell and shutter protected the media as compared with the industry-standard 5.25" floppy. Wendell Sander and Bob Bailey, with help from Ron Nicholson, designed a single-chip integrated floppy controller called the "Integrated Woz Machine" (IWM) [Ref-4: '448 patent]. The IWM chip exactly implemented the state machine of Steve Wozniak’s ingenious Apple II floppy disk controller design, which had already dramatically reduced the number of chips used as compared with earlier floppy disk controllers. This IWM chip thus maintained compatibility with older Disk II media, and also supported the faster 3.5" micro-floppy drive which used the more complex system clock of the Macintosh.

The Sony 3.5” micro-floppy was uniquely enhanced for the Macintosh by incorporating performance, capacity and data integrity improvements which had been prototyped with a 5.25" floppy [SJMN Twiggy Mac story] by way of five innovations. First, media capacity was increased from the stock 256 KBytes to 400 KBytes by (a) replacing Sony's standard Modified Frequency Modulation (MFM) encoding with Group Code Recording (GCR) encoding, and (b) by running the motor at one of 400 possible speeds between 390 and 600 rpm in order to maintain the same linear velocity throughout the disk, thereby allowing more data sectors on the outer tracks. George Crow redesigned Sony's micro-floppy drive circuitry to make the variable motor speed possible, and the hardware to control the motor speed was cleverly minimized by Burrell Smith, Andy Hertzfeld and Larry Kenyon by way of a channel of the sound generator and using software noise shaping (filtered dithering) for the Sony disk speed control DAC [Ref-2: '670 patent]. Second, high-speed sequential data transfers were effected using Steve Wozniak's sector interleaving scheme as implemented by Andy Hertzfeld and Larry Kenyon. Third, improved on-the-fly GCR data encoding and decoding was designed by Rich Williams and implemented by Larry Kenyon. Fourth, data integrity was improved using an error detection system developed by Dick Woolley, Neal Glover and Rich Williams [Ref-7: '941 patent], a method that replaced the simple checksum used by most other floppy drives. Fifth, the software-controlled floppy clamping and eject mechanism [Ref-3: '033 patent] - a signature characteristic of the Macintosh - insured file system integrity upon ejection of the floppy disk. The one-chip controller in combination with these five innovations created a fast, high capacity, reliable and low-cost storage device that was unique to the Macintosh. The Macintosh micro-floppy is also discussed on pp. 32, 39-42, 54 and 66-68 of the February 1984 issue of Byte magazine (see URL at bottom of page).

The detached keyboard was designed by Daniel Kottke and Ed Riddle. It was an appealing part of the Macintosh design, especially as it used a modular phone-style coil cord. Daniel Kottke also built about a dozen prototype versions of the main logic board over the course of the Macintosh's development cycle in 1982 and 1983.

Burrell Smith created a novel high-performance sound generation system without the need for sophisticated hardware by (1) placing sound samples in a buffer just after the display's vertical retrace interrupt, (2) using the Motorola 68000's 32-bit registers to control pitch with 24 bits of precision (resulting in 16,777,216 possible frequencies), and (3) passing sound data through a software-controlled volume adjustment that created approximately 20 dB of total amplitude variation in eight discrete steps. Burrell Smith describes this sound generation system in [Ref-2: '670 patent], [Ref-6: '414 patent] and in a portion of his "Macintosh System Architecture" treatise on p. 32 of the February 1984 issue of Byte magazine (see URL at bottom of page).

The introduction of the Macintosh built on partnerships with software developers - led by Guy Kawasaki’s “Evangelism” team - and with universities, to rapidly build a viable ecosystem of third-party software and hardware add-ons, and of dramatic and useful applications and research.

The common GUI amongst Macintosh applications was enabled by the Macintosh Toolbox, and the decision to put the toolbox into ROM was made practical by the innovative use of the Motorola MC68000's A-Line emulator trap instruction which allowed ROM patching. Andy Hertzfeld provided background for this on p. 38 of the February 1984 issue of Byte magazine (see URL at bottom of page): "It is somewhat risky to put 64K bytes of intricate system software in ROM on a disk-based system, but we did it because we wanted the machine to have a built-in standard user interface. By using our ROM-based toolbox, a programmer saves development time and precious memory space; this provides a positive incentive for doing it our way. Also, the price per bit of ROM is significantly less than that of RAM, and not having the operating system load in from disk saves space on every disk you have. Application programs never reference the ROM directly; instead, they use compact 'trap' instructions that are interpreted by the system dispatcher. This allows us to intercept any routine to fix the program bugs that will inevitably arise."

The Macintosh quickly became a popular platform for creative users, as well as for education, research and business applications. The higher bar of an affordable high-resolution GUI, and a standardized operating system and user interface toolkit, became the new standard against which competitors had to compete. Thus, end users came to expect, and the industry was challenged to offer, more advanced capabilities in low-cost systems.

What obstacles (technical, political, geographic) needed to be overcome?

Building a personal computer with a high-resolution bit-map display, integrating a mouse and a GUI, and being able to sell it for less than $3,000 required a new approach in an era where the least-powerful low-volume alternative products were expected to be available for perhaps $15,000 or more. It was thus a challenge to (1) envision and design the product packaging, including a mouse and keyboard, and (2) create an inexpensive, low parts count (< 50 logic ICs including RAM and ROM) single-board computer that could drive an integrated bitmap display and support a GUI.

After a number of “dead ends” with alternative disk drives, the Macintosh team chose and quickly integrated the Sony 3.5” hard-shell micro-floppy drive. This was a little-known drive and storage medium, in relatively early stages of development, whose use in the Macintosh kicked off much broader adoption in the industry as well as much success for Sony with this product line.

The development tool-chain, operating system, Application Programming Interfaces and related documentation was mostly developed from scratch, though an extended form of Pascal was used (in conjunction with Motorola 68000 assembly language), and some tools were adopted from and improved from those used for the Apple Lisa computer.

The Macintosh team proper was often in a challenging relationship with the parent Apple company, whose main line of business at the time was making and selling Apple II and related products.

Designing and envisioning a new way of working with software developers and (potential) large customers such as universities catalyzed the innovative creation of the “Evangelism” processes and team under Guy Kawasaki. Apple had to persuade customers and developers to take a big risk in committing resources to the Macintosh. Those who in fact joined found that these risks paid off very well in the end.

What features set this work apart from similar achievements?

The Macintosh became best known for its graphical user interface (GUI) which made use of WIMP (Windows, Icons, Menus, Pointer) with a bitmap display. WIMP systems that preceded the Macintosh include the Xerox Alto (1973), Xerox Star (1981), Apollo Computer Display Manager (1981), Carnegie Mellon University’s Andrew Project (for Unix, 1982), Rob Pike’s Blit terminal (for Unix, 1982), Sun Microsystem's SunView (early 1980s, for Sun's SunOS Unix; originally SunTools), Apple’s Lisa (1983) and W (1983 and earlier). Six months after the Macintosh was introduced and rolled out in January 1984, W evolved into X at MIT, and this matured into the X Window System (aka X-Windows) whose use continues to this day. Microsoft's first WIMP product was Windows 1.0, released on November 20, 1985.

The success of the Macintosh was primarily due to the fact that it was an affordable device that included WIMP and a bitmap display. The foundation for this success is due to at least these ten key accomplishments, as made possible by their respective “champions”:

1. Inspired by Steve Wozniak's design approach to the Apple I and Apple II, and working with Andy Hertzfeld and the software team, Burrell Smith created a minimalistic yet high-performance personal computer which he nicely summarizes in his "Macintosh System Architecture" treatise on p. 32 of the February 1984 issue of Byte magazine (see URL at bottom of page). In addition to its use of a (RAM-driven) bitmap display and a one-button mouse to provide a graphical user interface (GUI), the Macintosh was also able to be networked through inventions by Gursharan Sidhu and his AppleTalk (later called LocalTalk) team, and was also able to handle sound input and output.

2. Multiple innovations based on Sony's 3.5" micro-floppy drive resulted in a fast, high capacity, reliable and low-cost storage solution that was unique to the Macintosh. The floppy controller was a single-chip integrated version of Steve Wozniak's Apple II disk controller which cost-reduced a disk interface that was already less expensive than MFM disk controllers while improving performance. The controller chip was specified by Wendell Sander and was designed by Bob Bailey (then of Synertek) [Ref-4: '448 patent]. The Macintosh team created five innovations for this controller chip and the drive: (1) data capacity was increased from 256 KBytes to 400 KBytes by replacing MFM with GCR encoding and by changing the motor speed to maintain the same linear velocity for all the data sectors using Sony micro-floppy drive circuitry that was redesigned by George Crow, and motor speed hardware control [Ref-2: '670 patent] that was cleverly minimized by Burrell Smith, Andy Hertzfeld and Larry Kenyon, (2) Andy Hertzfeld and Larry Kenyon implemented Steve Wozniak's sector interleaving scheme for high-speed sequential data transfers, (3) improved on-the-fly GCR data encoding and decoding was designed by Rich Williams and implemented by Larry Kenyon, (4) data integrity was improved using an error detection system developed by Dick Woolley, Neal Glover and Rich Williams [Ref-7: '941 patent], and (5) the signature characteristic of the Macintosh's floppy was implemented using a software-controlled clamping and eject mechanism [Ref-3: '033 patent].

3. After a detour into trying to build a massive full-custom VLSI glue chip (working with Martin Haeberli and Brian Howard and a team at VLSI Technology), Burrell Smith was independently able to figure out how to drive PAL technology to get a then-amazing 16 MHz pixel clock out of the built-in video controller. In addition, Burrell created a novel high-performance sound generation system without the need for sophisticated hardware as described in [Ref-6: '414 patent] and in his "Macintosh System Architecture" treatise on p. 32 of the February 1984 issue of Byte magazine (see URL at bottom of page).

4. Bill Atkinson invented QuickDraw [Ref-5: '545 patent], first for the Apple Lisa and then in an expanded form for the Macintosh. This hugely success application was inspired by Bill’s visit to Xerox PARC in 1979 - see Oral History of Andy Hertzfeld and Bill Atkinson via URL at bottom of page. As Bill was at least initially unaware that the BitBlt graphics code for the Xerox Alto (originally written by Dan Ingalls) was done in microcode, he didn't realize the difficulty of getting high-performance graphics built for the Motorola 68000.

5. Bud Tribble and Andy Hertzfeld, working in conjunction with Bill Atkinson (the author of QuickDraw and later of HyperCard), designed an operating system that although it was implemented in ROM, was uniquely designed to permit its elements to be enhanced, replaced and repaired in order to fix bugs and/or to extend its capabilities. Programming interfaces were exposed in both Pascal and assembly language (as documented, e.g., in Inside Macintosh; see URL at bottom of page).

6. The Macintosh was the first technology product to have a "Software Evangelist," a moniker coined by Mike Murray. Mike Boich hired Guy Kawasaki, and Guy reported to him during the time of the Mac's introduction. They both carried out the duties of promoting the radically new product features. Not long after the Mac's introduction, Guy became "Software Evangelist" and Mike moved on to other roles. Guy's approach proved to be profoundly effective in getting software developers to write third-party applications for the Macintosh.

7. The rapid customization and localization of Macintosh software was made possible by the Resource Manager (invented and developed by Bruce Horn), which all applications were encouraged and eventually required to use. This approach separated out the language and graphical design of the user interface from applications proper so that applications could quickly be translated and converted to other languages and cultures.

8. Inspired by Rod Holt, George Crow designed the first integrated high-resolution video display and switching power supply on one single-sided printed circuit board (PCB). The challenge of preventing the switching power supply from injecting noise into the video circuitry was overcome by way of a painstaking component layout process for this PCB.

9. Another big innovation was the user manuals. Chris Espinosa, Lynnea Johnson, Carol Kaehler and others, under the intense guidance of Steve Jobs, invented a new class of books for users. They were clean, simple, direct, graphical, colorful, and easy to read. In particular, the Macintosh User's Guide by Carol Kaehler established a new kind of book to introduce the personal computer to a user who had never touched one before. This was a big departure from the materials previously made for hobbyist computers. Caroline Rose wrote the spectacular three-volume Inside Macintosh series that documented the system calls that developers needed to use. Without Inside Macintosh, the flowering of third-party applications would not have happened. Developers had never programmed for a graphical user interface, and were completely unfamiliar with how the Mac worked. The clarity and timeliness of Inside Macintosh allowed third-party developers to quickly build applications for desktop publishing and many other areas.

10. The Macintosh Toolbox was a huge advance since applications were able to build on the toolbox code, and over 80% of execution took place in the toolbox for some applications. Putting this well-tested code in ROM (alongside the ROM-based operating system) on a limited memory system all but guaranteed that developers would use it, contributing to an unprecedented consistency of user interface, and thus learnability, among third-party applications. This approach, which was in contrast with third-party developers having to code their own user interface, cemented the Mac's unique hallmark of a consistent application GUI. Andy Hertzfeld wrote most of Macintosh Toolbox. He had help from Steve Capps and others, and it was based on work that Bill Atkinson had done for the Lisa.

Molded on the inside of the case of the original Macintosh are the signatures of these 48 members of the early 1982 Macintosh Division of Apple Computer: Peggy Alexio, Colette Askeland, Bill Atkinson, Steve Balog, Bob Belleville, Mike Boich, Bill Bull, Matt Carter, Berry Cash, Debbie Coleman, George Crow, Donn Denman, Christopher Espinosa, Bill Fernandez, Martin Haeberli, Andy Hertzfeld, Joanna Hoffman, Rod Holt, Bruce Horn, Hap Horn, Brian Howard, Steve Jobs, Larry Kenyon, Patti King, Daniel Kottke, Angeline Lo, Ivan Mach, Jerrold Manock, Mary Ellen McCammon, Vicki Milledge, Mike Murray, Ronald H. Nicholson, Jr., Terry Oyama, Benjamin Pang, Jef Raskin, Ed Riddle, Brian Robertson, Dave Roots, Patricia Sharp, Burrell Smith, Bryan Stearns, Lynn Takahashi, Guy "Bud" Tribble, Randy Wigginton, Linda Wilkin, Steve Wozniak, Pamela Wyman and Laszlo Zidek.

Supporting texts and citations to establish the dates, location, and importance of the achievement: Minimum of five (5), but as many as needed to support the milestone, such as patents, contemporary newspaper articles, journal articles, or chapters in scholarly books. 'Scholarly' is defined as peer-reviewed, with references, and published. You must supply the texts or excerpts themselves, not just the references. At least one of the references must be from a scholarly book or journal article. All supporting materials must be in English, or accompanied by an English translation.

Patents referenced above are Ref-1: '652 patent, Ref-2: '670 patent, Ref-3: '033 patent, Ref-4: '448 patent, Ref-5: '545 patent, Ref-6: '414 patent and Ref-7: '941 patent. Also included is a 12 September 2013 story from the San Jose Mercury News about the Twiggy Mac, a prototype version of the Macintosh which included a 5.25" floppy drive before the 3.5" micro-floppy drive was available. In addition, the 1984 book Inside Macintosh, Volume I, the Macintosh cover story of the February 1984 issue of Byte magazine (Vol. 9, No. 2) and the Computer History Museum Oral History of Andy Hertzfeld and Bill Atkinson are referenced.

Supporting materials (supported formats: GIF, JPEG, PNG, PDF, DOC): All supporting materials must be in English, or if not in English, accompanied by an English translation. You must supply the texts or excerpts themselves, not just the references. For documents that are copyright-encumbered, or which you do not have rights to post, email the documents themselves to ieee-history@ieee.org. Please see the Milestone Program Guidelines for more information.

Apple Macintosh Reference 1 (Ref-1): US Patent 4,464,652 ('652 patent) "Cursor Control Device for Use with Display Systems"; Inventors: William F. Lapson and William D. "Bill" Atkinson; filed 19 July 1982; issued 7 August 1984. Ref1-US4464652.pdf‎

Apple Macintosh Reference 2 (Ref-2): US Patent 4,910,670 ('670 patent) "Sound Generation and Disk Speed Control Apparatus for Use with Computer Systems"; Inventors: Burrell C. Smith and Andrew J. "Andy" Hertzfeld; filed 19 May 1987 (continuation of 20 January 1984 application); issued 20 March 1990. Ref2-US4910670.pdf

Apple Macintosh Reference 3 (Ref-3): US Patent 4,466,033 ('033 patent) "Disk Drive with Automatic Disc Clamping and Ejecting"; Inventors: Richard Jordan, William Bull, Robert L. Ciardella, Robert Taggart and Frederick R. Holt; filed 24 February 1982; issued 14 August 1984. Ref3-US4466033.pdf

Apple Macintosh Reference 4 (Ref-4): US Patent 4,742,448 ('448 patent) "Integrated Floppy Disk Drive Controller"; Inventors: Wendell B. Sander and Robert Bailey; filed 18 December 1986 (continuation of 24 January 1984 application); issued 3 May 1988. Ref4-US4742448.pdf

Apple Macintosh Reference 5 (Ref-5): US Patent 4,622,545 ('545 patent) "Method and Apparatus for Image Compression and Manipulation"; Inventor: William D. "Bill" Atkinson; filed 30 September 1982; issued 11 November 1986. Ref5-US4622545.pdf‎

Apple Macintosh Reference 6 (Ref-6): US Patent 4,445,414 ('414 patent) "Digital, Simultaneous, Discrete Frequency Generator"; Inventor: Burrell Smith; filed 24 February 1982; issued 1 May 1984. Ref6-US4445414.pdf‎

Apple Macintosh Reference 7 (Ref-7): US Patent 4,564,941 (‘941 patent) "Error Detection System"; Inventors: Richard N. Wooley, Neal Glover and Richard Williams; filed 8 December 1983; issued 14 January 1986. Ref7-US4564941.pdf

San Jose Mercury News story of 12 September 2013: "Apple's Mac team gathers for insanely great Twiggy Mac reunion." SJMN-TwiggyMacReunion(12-Sep-2013).pdf

The 1984 book Inside Macintosh, Volume I is available at https://archive.org/details/bitsavers_applemacIn84_27699101

The Macintosh computer is the cover story of the February 1984 issue of Byte magazine (Vol. 9, No. 2), and this issue includes two Mac stories: "The Apple Macintosh Computer" on pp. 30-54, and "An Interview: The Macintosh Design Team" on pp. 58-80. This same issue, which also includes the story "Apple Announces the Lisa 2" on pp. 84-85, is available at https://archive.org/details/byte-magazine-1984-02

Computer History Museum Oral History of Andy Hertzfeld and Bill Atkinson; Interviewed by Grady Booch on 8 June 2004. Transcript available at http://archive.computerhistory.org/resources/access/text/2013/05/102658007-05-01-acc.pdf

Please email a jpeg or PDF a letter in English, or with English translation, from the site owner(s) giving permission to place IEEE milestone plaque on the property, and a letter (or forwarded email) from the appropriate Section Chair supporting the Milestone application to ieee-history@ieee.org with the subject line "Attention: Milestone Administrator." Note that there are multiple texts of the letter depending on whether an IEEE organizational unit other than the section will be paying for the plaque(s).

Please recommend reviewers by emailing their names and email addresses to ieee-history@ieee.org. Please include the docket number and brief title of your proposal in the subject line of all emails.