The internet has radically transformed how we build and promote businesses: We have access to far more resources and far more potential than ever before. So, why do so many entrepreneurs end up neglecting these fruitful opportunities by forgoing marketing, or delaying it as an unnecessary expenditure?

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The way I see it, there are a handful of online marketing strategies you need -- as in, your startup won’t be able to thrive without them.

Criteria for “need”

What do I mean, you “need” these strategies? After all, isn’t marketing optional? Isn’t it possible to build a business even without an online presence? Technically, yes, but you’ll be missing out on enormous potential by doing so.

All the strategies I qualify as “necessary” exhibit the following traits:

  • Expected. People expect you to have these things in place, and if you don’t have them, they may think less of your company.
  • Accessible. None of these strategies is particularly hard or complicated; there may be a bit of a learning curve, but on some level, these are accessible strategies.
  • Affordable. You won’t have to spend much money on any of these strategies, making them easy to pick up even for tight-budget startups.
  • Valuable. These strategies all offer high potential returns, meaning that the cost for you, if you neglect them, will be significant potential.
  • Time-sensitive. The more time you invest in these strategies, the more powerful they become. The sooner you get involved, the bigger the payoff you can potentially get.

It’s the combination of these factors that makes your work in these areas necessary. These are the strategies I deem “necessary”:

1. Personal branding.

Successful businesses can generate a ton of momentum from successful entrepreneurs who lead them. Branding yourself, before your company, gives you the opportunity to leverage a more trustworthy, personal image to promote your brand.

It also gives you more power to meet and network with others, form more partnerships and lend a face to your otherwise faceless organization. And it's free to do, from a monetary perspective, though you will need to invest a significant amount of time.

2. Content marketing.

Content marketing takes a variety of forms, and depending on how you form your strategy, could accomplish a number of different goals. For example, you could use white papers, ebooks and other long-form content to attract downloads, signups and conversions, or you could use an on-site blog to attract more inbound traffic to your site.

You could even use content as a form of help and troubleshooting, or some combination of these applications. Content marketing is incredibly versatile and useful, and, if it's valuable, your customers will expect you to have at least some of it in place for them.

Related: 5 Ways to Improve Your Content Marketing Results Without Breaking the Bank

3. Search engine optimization (SEO).

SEO is the process of making your site more visible in search engines, so you get more traffic from people searching for the products or services you offer. Much of your organic search position ranking comes from the technical structure of your site and your ongoing content development strategy.

So, SEO is not much more of an investment if you’re already creating new content regularly -- and it’s well worth that extra investment if for no other reason than to make sure your site is properly indexed.

4. Conversion optimization.

Most of these strategies aim to get more people on your site, but what do those people do once they’re there? Conversion optimization helps you ensure you get more value out of each and every visitor by maximizing your rate of conversion.

Sometimes, this means including more conversion opportunities, and other times, improving the ones you already have.

5. Social media marketing.

Social media marketing isn’t the get-rich-quick scheme you may have been promised, but there is significant potential in building and nurturing a social media audience. Again, content will come into play heavily here, as it will likely be the factor that attracts your audience to begin with. Here, you stand to gain greater brand visibility, a greater reputation and far more inbound traffic with your syndicated links.

6. Email marketing.

Email marketing has astounding potential for ROI because it costs almost nothing to execute. Start collecting subscribers from your existing customer base, your social media followers and other new opportunities; from there, even a simple content newsletter can help you encourage repeat traffic to your site, facilitate more engagement with your brand and keep your brand top-of-mind with your audience.

Related: The 4 Essentials of Video Content Marketing Success

As you may have noticed from these descriptions, there’s one other key advantage these strategies offer: They all work together. While they can be pursued individually, each connects with and feeds into the others in some way. If you pursue them all, complementing your efforts across these multiple areas, you’ll see an even higher potential return.