Memos contains searchable indices of the Physics, Engineering, Programming, and HAPPE Memos, as well as the memos themselves. The memos are dated from 1951 to 1990 (although there are only two memos before 1955 and six memos after 1986). About 65 Physics Memos and 50 Programming Memos that are missing from those files are so marked in these indices.

A number of memos (especially those that gave instructions for scanning bubble-chamber film or that described data-analysis programs) were revised. When a revised memo is in the file, it is its title, date, and author(s) that are given in the indices; these are often evident because their dates are later than those of neighboring memos. A number of memos have attachments, sometimes by other authors. No account of these has been taken in these indices — there are limits.

Abbreviations such as B.C. (bubble chamber) in the actual titles have been spelled out. Greek symbols have replaced anglicized Greek. Program names are in slant. Hyphens, semicolons, "the"s, etc., have been liberally inserted to make the titles more readable.

The memos themselves are available as PDF files at Memos. Rather than store all of the memos in individual files, they have been grouped into Physics, Engineering, Programming, and HAPPE Memos. The Physics, Programming, and HAPPE Memos have then been grouped ten to a file. The much fewer Engineering Memos are in just two files; one for the LA series and one for the M series. The memos are separated by a blank page between them.

The page images of the memo may be selected, copied, and pasted into any file which will accept images, such as MS Word, from which they can be saved with the Save As command.

The photos show the 72-inch bubble chamber and Luis Alvarez and his longtime secretary Ann McLellan.