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*Minolta was founded in 1928 as “Nichi-Doku Shashinki Shōten” (Japanese-German camera shop)*. After a line of rangefinder cameras modeled close to Leicas the company introduced it's first SLR camera in 1958, the SR-2 with the first Japanese bayonet mount. I'm referring to manual lenses from Minolta for this mount only, officially called SR, but most call it MC/MD these days. MC lenses (meter coupled) are the older ones, produced from 1966, but the only difference in MD mount from 1977 is a modified mechanical coupling for the aperture setting in the MD. The mount stayed compatible between all lenses until the very first autofocus camera was introduced by Minolta in 1985. Of course they continued to make some lenses for the older mount for quite a while after 1985. All lenses with this mount can be adapted to modern mirrorless cameras like µFT or NEX, but via an adapter from MD/MC to Leica-M you can mount it on RED's Leica-M mount just fine. None of these lenses expands beyond the mount, so there is no problem with this combination like there is with most Leica-M lenses wider than 50mm.
After trying to copy Leica all the time from 1958, they learned to do it so well that in 1972, they sub-contracted with Leica and drew up a formal cooperation agreement. “Leitz desperately needed expertise in camera body electronics, and Minolta felt that they could learn from Leitz's undoubted optical expertise.” (source: Wikipedia) Many of their lenses carry the name “Rokkor” (after the mountain Rokko near to their factory in Japan). In the US most were called Rokkor-X without being any different from the plain Rokkors sold elsewhere. In later years a budget line of lenses (called Celtic in the US) was introduced. Between 1979 and 1982 Minolta redesigned many lenses for lighter and more compact versions with a 49mm filter thread, using some plastics instead of metal. IMHO the older, heavier and more massive ones with a 55mm filter thread are the better built lenses. If treated well, focus and aperture are working as smooth as on the first day even after 40 years or more.
The optical quality of some of the redesigned ones from this period can be better, though (I'll get back to this when getting to individual lenses), and it was not before 1982 that even more plastic was used and cost reduction became an important factor for most of the lenses targeted at amateur markets. Apart from some very special, earlier gems the lenses from early to mid eighties can be recommended for being the best in coating and build. Starting from mid nineties pressure from third-party manufacturers started a massive decline in overall quality and increased sample variation – until then Minolta had pretty tight QC.
*The best index to identify a Minolta lens and it's age can be found here:*
http://minolta.eazypix.de/lenses/index.html
Watch out: some lenses can have significant differences in their optical design and quality (the 135mm tele for example) and are only identified by their precise weight and size. A two letter signature was only used for MC lenses and designated the number of lenses and groups in the particular lens.
The system goes like this:
Accordingly, the famous 58mm 1:1.2 MC Rokkor PG contains 7 elements in 5 groups.
Although there is no official explanation, it is easy to see the greek alphabet in the first code letter designating groups, Penta, Hexa, Septa, Okta, etc.
The second letter is probably just chosen by alphabetical order. Via http://minolta.rokkor.de/minoltalenses.htm
All classical lenses (without digital correction in camera bodies) are a complex optimization of different parameters, some of which can be contradictory. Minolta had a philosophy of not favoring only one parameter (like MTF) on the cost of another, like quality of bokeh (which was discussed among aficionados in Japan much earlier than elsewhere). Most important – in particular for us as filmmakers – is the consistency of color and contrast over the whole line of lenses Minolta was striving for by making their own glass and carefully balancing it's color with their coatings. Just like others, they improved coatings over the years and younger versions are in general less flare-prone than older ones, but they always maintained the Minolta look.
Leica (from whom Minolta learned a lot about optics) has never achieved such a level of consistency, they tried to make every single lens as good as possible – with remarkable results. But Summicrons for still cameras with a different number of elements can have quite different color and contrast (I'm not talking about their cine lenses here). Apart from that, the Minolta look is closer to Leica than Zeiss, which are also quite consistent in color (but not always for contrast) in lines like Hasselblad and Contax, just different. That's why I have quite a few of both Rokkors and Contax Zeiss lenses, while I don't have any Leica lenses. Some call Minolta lenses “poor man's Leicas” for a reason 
Film emulsion is not as reflective as the OLPF of a digital camera. This simple fact can make a big difference when older still lenses are used on digital sensors, since the manufacturers didn't put as much effort into the coating of the rear surfaces as today. You may see haloing if using fast lenses on a digital camera wide open. That said, I found a Nikkor 50mm 1.4 for example much weaker in this respect than a MC Rokkor PG 50mm 1.4 from the same era. This Rokkor, BTW, is one of the sharpest 50mm lenses I've ever tested, bested only by the Zeiss C/Y 50mm 1.7 (but not the 1.4!). The effect can be very different from lens to lens, it depends very much on the curvature of the back lens. Apart from this contrast reducing effect, these lenses are just as good on digital as on film. All wides are retro-focus constructions; being designed for SLRs, they don't expose the side effects some rangefinder lenses can show in the corners due to extreme angles of the light rays.
The most sought after (and accordingly pricey) lenses are the 85mm 2.8 Varisoft, the 24mm 2.8 VFC and the 35mm 2.8 Shift CA lens. The Varisoft is a specialized portrait lens whose spherical aberration correction can be adjusted between a very sharp image with rather nervous bokeh and a very dreamy look like from a fashion magazine of the sixties (similar, but not quite the same as the expensive Nikkor DC = Defocus Control). The VFC (Variable Field Curvature) lens is a very good wide at neutral, but it's field of focus can be adjusted to be concave or convex. Obviously, the effect is not as strong on a RED as on photographic full-frame. The Shift CA has a similar VFC adjustment plus a very precise shifting mechanism and if you've ever asked yourself, how you can shoot a CU as if looking straight into a mirror without being seen: here you go! Initially it was meant for architecture to avoid too much perspective inclination of vertical lines. A mechanical masterpiece.
*Over the next few posts I'm going to introduce a few other, more daily work favorites of mine.*
Until then, there is a lot of information in English here: http://www.rokkorfiles.com and here: http://digitalrokkor.altervista.org/minoltalens.html (scroll down for English)
and some in German: