Algeria is a country in Northern Africa.
Algeria has generally a mutual visa policy, that means that, generally, they apply to the citizens of any country the same policy that country applies to Algerian citizens.
Working and studying visas require invitations from the local institution (university or company) while tourist visa can be obtained both with an invitation from a local person (to be validated at local police station and which imply some responsibilities for the inviting person) or following the travel agencies procedures (that should be better done by a travel agency..): - entrance/exit ticket reservations, hotel booking, travel insurance, bank account/demonstration of having money and other documents according to the place you are applying from.
Most often the visa can be obtained only in the country where your residence is, that means that making it "on the road" is almost impossible, unless you are working and living for a long period in some place.
Depending of course from the personnel working in the different embassies/consulates but they are often not really welcoming and quite suspicious, especially if you don't have a job, a regular life and so on (may be useful lie about your profession, say you are student, etc).