On Discrimination and the Elusiveness of Equality
In its broadest sense, discrimination just means recognising a difference between things, or people. In its more common sense, it is used to refer to treating someone differently because of differences which are probably irrelevant in context. For example, racial discrimination might include a tendency not to give people job interviews if they have names associated with black people; sex discrimination would include a tendency to promote men at the expense of equally qualified women. People are also known to discriminate based on class, religion, country of origin, politics, disability, age, appearance and sexual orientation - indeed, almost anything that makes anyone noticeably different.
As long as the basis of the discrimination is indeed irrelevant, it is not only unjust but also inefficient, objectively resulting in the wrong people attaining the best positions.
In the last half-century, great strides have been made towards reducing this sort of discrimination in English-speaking countries, and other parts of the world. Discriminatory laws have been repealed, and new laws have been introduced to ban sex or race discrimination in the workplace. In some places it is also illegal to discriminate based on religion, sexual orientation or gender identity. There is no doubt that these changes have made life very much better for people with characteristics that have historically attracted discrimination, and they have almost certainly been good for the economy at large, since they prevent people from making certain counter-productive economic decisions.
However, the fight for equality goes much deeper than just fighting against discrimination, because there is way more to privilege than that. On average, women are still paid far less than men, and blacks are still paid far less than whites, for reasons which can not entirely be blamed on discrimination as such. That is not to say those reasons are any good, or that discrimination is a thing of the past, but there is a lot more to the story.
Women in the UK and North America are now usually paid as much as men for identical jobs - however, the kinds of jobs that women do are overwhelmingly paid worse than the kinds of jobs that men do. The underlying reasons for this are undoubtedly partly sexist, many of them stemming from discriminatory education and conditioning, but they are also a facet of the general idiocy of our current economic system when it comes to fairly compensating worthwhile work. One aspect of this is that professions full of people who are motivated by something other than money and power, like a desire to help people, tend to be paid worse - even if they take more work and are valued at least as highly by other people. They also attract more women than professions with little going for them besides status and salary, presumably for cultural reasons.
The reasons for black people doing worse, economically, than their lighter-skinned peers have a great deal to do with inherited wealth - and its flipside, inherited poverty. If your ancestors were robbed, abused and kept down by the ruling class, and you live in an economic system where people are far, far likelier to do well if their parents were well-to-do, you are going to start with a major disadvantage in life, whatever people think about your skin colour. For this reason, the fight against racism, like the closely related fight for equality among castes in India, has considerable overlap with the fight against classism. Capitalism and inheritance are enormous barriers to economic equality in all of these cases.
In short, there is a big difference between equality of opportunity and actual equality. This is why 'positive discrimination' has sometimes been encouraged in the workplace and in educational institutions: to give people a fair chance, you need to acknowledge the disadvantages they start out with. Once again, this can be argued in terms of efficiency as well as justice. If you are looking for intelligent people, and you know that equally intelligent kids are likely to do worse at school if they come from disadvantaged backgrounds, it makes sense to look more favourably on disadvantaged kids with equivalent qualifications. Positive discrimination of any sort runs a serious risk of fostering resentment, however, and the suspicion that someone only got to the position they are in because of their background.
The fight against discrimination carries on, and in much of the world it has hardly begun. The fight for equality has even further to go.