Does Reading a Diary Entry Load Its Remote Image Again?
Usually, a diary entry that contains an image URL can cause the app or browser to request that image when it displays the entry. But that does not mean the image is downloaded from the remote server every time: a valid browser cache may supply it, or the app may handle images in another way. The practical first check is whether the entry points to a web URL or to an image saved with the diary. An offline test can offer clues, but it cannot prove that no network request occurred.
What does an image link in Markdown mean?
In standard Markdown, image syntax such as `` identifies an image by its URL. The [CommonMark image tutorial](https://commonmark.org/help/tutorial/08-images.html) explicitly shows complete web URLs as valid image destinations. The syntax itself does not say that the image has been copied into the diary or stored locally.
When a reader displays that entry, the software may render the URL as an image source. In a web page, the browser’s `<img>` element embeds an image in the document, and its `src` attribute identifies the resource to display, as described in [MDN’s `<img>` reference](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/img). Whether a request reaches the remote server depends on caching and the particular app, browser, and network path.
Does the browser contact the server on every read?
No fixed rule says it must fetch every image afresh. Browsers check their HTTP cache when making requests; if there is a matching, valid cached response, the browser can use it without contacting the origin server for that image. [web.dev’s HTTP cache guide](https://web.dev/articles/http-cache) explains that freshness depends on response caching information and that a cached response can be reused while it remains fresh.
If a cached response is stale or requires validation, the browser may contact the server to check whether the stored copy is still current. The server can confirm that the copy remains valid, so this check need not mean the full image was downloaded again. [MDN’s HTTP caching guide](https://developer.mozilla.org/en-US/docs/Web/HTTP/Guides/Caching) covers freshness, validation, and cases where responses should not be cached. Cache clearing, expiration, changed URLs, app behavior, or cache settings can all change what happens on a later read.
So the careful answer is: displaying a remote image may lead to a network request, but it does not necessarily transfer the image bytes each time—or contact the origin on every view. A cached display and a fresh fetch can look identical on screen.
How can you tell a URL from a saved attachment?
Inspect the image reference or the app’s attachment information, if it exposes one. A destination beginning with `https://` or `http://` points to a remote web address. A relative path or app-specific attachment name needs more checking. In a web page, a relative path can resolve to another web address; it does not prove a file is local to your device. The diary app’s storage and rendering rules determine the destination. Markdown alone does not guarantee that a local-looking reference is portable or that the file is stored inside the entry.
A useful distinction is what must remain available: a remote URL depends on the remote resource continuing to exist and being reachable; a local attachment depends on the relevant file being present where the app expects it. For preserving diary photo files, follow the app’s own export or backup instructions. This article’s focus is the separate question of remote loading, not a guarantee about any particular app’s storage format.
What can an offline comparison show?
For a harmless check, use a non-sensitive image URL in a disposable test entry. View it while online, then disconnect the device from the network and reopen the entry. If the image appears offline, that is consistent with a cached copy or another local copy being available. If it does not, the app may need the remote resource at that point—but the result alone does not identify exactly why.
This comparison cannot establish that normal online reading makes no network requests. The browser might have made a request before disconnection, checked a service-worker or application cache, or displayed an image already stored locally. Likewise, seeing the image while offline does not prove the entry’s Markdown contains an attachment: the app could have cached the remote response. For a browser-based diary, observe request behavior using the browser’s network developer tools while online and inspect the image request and its cache status; results describe that test setup, not every later read or device.
Practical checklist
For an entry that must display predictably, inspect the image reference, then check whether the corresponding local attachment exists if it is meant to be local. If it is a remote URL, expect availability and update behavior to depend on the host and caching. Use an online network panel to observe requests and an offline reopen as a limited comparison. Treat each result as evidence about the tested app, browser, and cache state—not as a universal guarantee.