Purchasing Grand Theft Auto V (GTA V) on Steam is a straightforward process. Follow these steps to secure your copy of this popular game:

1. Create a Steam Account: If you don’t already have one, visit Steam and sign up for an account. Fill out the necessary details and verify your email address to activate the account.

2. Download the Steam Client: Log into your account on the Steam website and download the Steam client. Install it and log in with your account credentials.

3. Search for GTA V: Using the search bar in the Steam client or on the website, type "Grand Theft Auto V" to locate the game. Click on the correct search result to go to the store page for GTA V.

4. Check System Requirements: Make sure your computer meets the game’s system requirements listed on the store page to ensure a smooth gaming experience.

5. Purchase the Game: Click the 'Add to Cart' button. Once in the cart, proceed to checkout. Steam accepts various payment methods including credit cards, PayPal, and other local payment options depending on your location.

6. Download and Install: After purchase, GTA V will be added to your Steam library. Navigate there, click 'Install', and follow the prompts to download and set up the game.

7. Start Playing: Once the installation is complete, you can launch the game from your library and begin your adventures in Los Santos.

Remember to take advantage of any promotions or discounts Steam may offer. Ensure your internet has enough bandwidth and storage space available for a seamless download process.