Why companies run an ERP

Meet Contoso Motor Co., the fictional company you will follow through every course in the Academy. Contoso is a US manufacturer of alternators for commercial vehicles. It builds alternators at its main plant in Detroit, keeps a second plant in Chicago, buys copper, steel and electronics from suppliers, and sells finished alternators and spare parts to vehicle makers and fleet operators.

Ten years ago, Contoso ran each department on its own software. Sales took orders in a customer system and a lot of spreadsheets. Purchasing had a separate buying tool. The warehouse tracked stock in yet another system. Accounting ran a standalone general ledger package. Each tool worked well for the people who used it every day. The trouble started in the gaps between them.

What life looks like with departmental silos

Picture one ordinary order. A fleet customer orders 40 alternators. Sales types the order into the sales tool. The warehouse learns about it from an emailed export and keys it again into the stock system. When the alternators ship, someone sends a shipping list to accounting, who keys the invoice into the ledger package. The same 40 alternators have now been typed three times, by three people, on three different days.

Every time data is re-keyed, two things can go wrong. A person can type it wrongly (40 becomes 4, or the price comes from last year's list), and the copies drift apart in time (the warehouse shipped on Friday, accounting posted on Tuesday). At month-end, finance spends days reconciling: comparing what each system says, finding the differences, and deciding which one is right.

What an ERP changes

ERP stands for enterprise resource planning. Strip away the jargon and an ERP system is one application, on one database, that the whole company uses to run its core business: selling, buying, making, storing, paying, and accounting. When sales creates an order, the warehouse sees the same order. When the warehouse ships, accounting is updated in the same moment, because the shipment and the accounting entry are recorded by the same system.

The key idea is enter once, use everywhere. Customer data, product data and prices live in one place, called master data. Business events such as orders, shipments and invoices are recorded once as documents. Every department works from the same records, so there is nothing to re-key and much less to reconcile.

Where SAP fits

SAP is a German software company founded in 1972, and its ERP products are among the most widely used in large and mid-sized companies. Its current ERP product is SAP S/4HANA. When people in a company say "we're on SAP" they usually mean the ERP system, even though SAP also sells many other products. In this Academy, "SAP" on its own means SAP S/4HANA unless we say otherwise.

Modules: the words you will hear

Inside SAP, functionality has traditionally been grouped into modules with two-letter names. You will hear them in every project meeting: SD (Sales and Distribution), MM (Materials Management, covering purchasing and inventory), PP (Production Planning), QM (Quality Management), PM (Plant Maintenance), FI (Financial Accounting) and CO (Controlling, meaning management accounting). SAP’s current material often talks in business areas such as Sales, Sourcing and Procurement, Manufacturing and Finance instead, but the module names are still everyday shorthand.

The catch is that modules are a way of organizing software and teams, not a description of how work flows. A single customer order touches SD, MM, FI and CO. That is why the next lesson describes the business in terms of end-to-end processes that cut across modules.

ERP does not remove every other system. Contoso still uses a separate tool for designing alternators and a website for spare-parts orders. But the transactions that move money and goods, and the records that end up in the financial statements, all run through the ERP. That is why it sits at the center of most IT landscapes and why changes to it are taken so seriously.

There is a cost to this. Because everything is connected, a mistake in one place spreads everywhere. A wrong price in the master data does not just affect one invoice; it affects every order that uses it. That trade-off, more integration in exchange for more care, is the thread that runs through the rest of this course.