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A ledger is a table that records monetary trasactions, as credit or debit, and is always indexed in a chronological way, by date and time. It is used since ancient times to log account transactions and tell and reconstruct the history of events on that account.

Ledger is a fundamental data management tool implemented in systems of banks and financial institutions. Before computer systems, banks already used ledgers as regular paper books to manage their clients accounts.

Here is an example of a ledger recording transactions that happened on an account…


Anaconda isn’t free anymore, for commercial use. It was about time to see the drug dealer that just makes UI candy to start charging for the candy that people got addicted to, that we don’t need (installation interface in this case).

Google Collab isn’t free neither. And it lives in the cloud, probably far from your data. And it is just a data exploration tool (as Jupyter), not production environment.

Not to mention that Anaconda is technically problematic and presented issues in many student’s laptops that I’ve seen. Yes, I collected some statistics in large classes. Not to mention that…


Se você está numa encruzilhada para escolher uma linguagem de computador para aprender a programar, escolha Python.

Python é espetacular para desenvolvimento web com seus frameworks Django, Flask, Web2py e muitos outros. Python é A linguagem para trabalhar com dados, graças ao Pandas, Jupyter, SciKit e todo o trabalho que a comunidade de machine learning continua investindo nele. É uma linguagem de uso genérico, é moderna, é elegante, é fácil, é o trend.

Node (JavaScript) não vai tão longe, tem seu escopo muito fundamentado só na web e sua história (nasceu no browser) lhe conferiu características técnicas bizarras. …

Avi Alkalay

I'm an experienced hacker focusing lately on Data Science and Data Engineering. I've also done a lot of customer-facing IT activities, programming, teaching etc

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