E-commerce and cloud computing giant Amazon.com (AMZN -0.17%) is gearing up for its first-quarter earnings report, slated to drop after the closing bell on Thursday. Here's a quick overview of the three most important things Amazon will share with investors this week.

1. The usual numbers

Three months ago, Amazon provided some financial guidance for the first quarter. Net sales should stop somewhere between $56 billion and $60 billion, producing year-over-year growth of 10% to 18%. Operating income is expected to land between $2.3 billion and $3.3 billion, up from $1.9 billion in the year-ago period. These targets assumed a 2% top-line headwind from currency exchange effects, reflecting a stronger dollar in comparison to other major currencies.

Logo banner for Amazon Web Services.

Image source: Amazon.

The currency effect actually intensified in February and March, at least in terms of translation from euros to dollars. In other words, the actual revenue results might come in a few percent below management's best guess in January.

2. Free cash flow

The headline numbers above are a good start, but Amazon itself prefers another metric. The company's stated long-term goal is to "optimize free cash flows." Amazon often produces far larger cash flow than bottom-line earnings. In 2018, for example, the company saw a total net income of $10.1 billion but free cash flow added up to $19.4 billion.

The company didn't offer guidance for this metric. For what it's worth, the second quarter of 2018 saw an outflow of free cash to the tune of $4.9 billion due to seasonal effects. The first quarter typically produces negative cash flow for Amazon as its inventories fall back after the hectic holiday season of each year's fourth quarter.

Here's the general trend in Amazon's trailing free cash flow over the last five quarters:

Bar chart showing how Amazon's trailing free cash flow developed in recent quarters.

Image source: Amazon.

3. Cloud computing

The collection of cloud computing services known as Amazon Web Services (AWS) accounted for 10% of Amazon's total fourth-quarter sales but 56% of the company's operating income. Moreover, this division posted 45% year-over-year sales growth compared to 20% for Amazon as a whole. AWS is Amazon's star player these days, and its results make a huge difference to the company's financial health.

Investors will be looking for continued skyrocketing revenue growth and juicy operating margin here, along with a fresh report on how Amazon is growing the market footprint and technical functions of AWS. The service regions under construction in Bahrain, Hong Kong SAR, Italy, and South Africa are currently expected to go live in the first half of next year; that rollout needs to stay on target.