'I have purchase a used 10.0 updated to 10.4 Tiger.', regardless of what you may have purchased - what is the version of MacOS X currently installed on your (unknown model) Macintosh?
To obtain the version number - click on the upper left blue 'Apple' menu and select 'About This Mac'. Below 'Mac OS X' is the complete (full) version number. Please reply with such.
As to the model number of your Mac - with the 'About This Mac' window still displayed, click on the 'More Info...' button. This will cause 'System Profiler' to open and display a window. It should display a 'Contents' column to the left and a large field, of information, to the right.
With 'Hardware' selected in the left side column, the right side should list 'Hardware Overview:' information. In this list of information locate, record, and reply with - the 'Machine Model:' and 'CPU Speed:'.
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'Anyhow, I don't have a clue as to how to put photos on my computer in order to send them to others.' What do you mean by 'put photos on my computer'? Are the photos ...
in a digital camera? (if so, what is the camera's manufacturer and model number?),
on a RAM disk (Thumb drive)?,
actual photos which need to scanned? (if so, do you have a scanner?, if so, what is the scanner's manufacturer and model number?),
on a CD / DVD?,
on another computer? (if so, are the two computers connected together or not?; if connected, are they connected via wire [Ethernet or Firewire] or wirelessly?; and, is the 'other' computer a Mac or PC [specify its manufacturer, model number, and operating system]), or
on the internet somewhere? (if so, what is the url [web page address]? - if viewable by the public)
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'The second problem is that I can't seem to insert a cd into the rounded slot on the front of the computer.', this at least tells me you have an (unknown model version) iMac. By 'I can't seem to insert a CD', are you implying a disc may already be inserted - but not displayed on the screen? - if so, restart (reboot) the iMac with the mouse button clicked (and kept clicked during the process), to force eject any non displayed inserted disc.
Open your 'Applications' and 'Utilities' folders. Place the two windows side by side, do a 'Command <shift> 3' and create a rectangle that covers both opened windows (make sure to have the windows sized to show all the items in each window). In your web browser - beneath 'macosx.com's 'Reply to Thread' area is the 'Additional Options' area, click on the 'Manage Attachments' button. When the 'Manage Attachments' window appears - click on the 'Choose File' button, do a 'Command D', and locate the 'Picture 1' file (or the highest numbered 'Picture' if others exist) created by the 'Command <shift> 3' process above, and then click on the 'Choose' button.
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By the subject title - 'Uploading photos and burning cd', 'uploading' means to send an item (or items) from your Mac to another device or to the internet. Is that what you want to do? - considering, that part of the title does not match anything within the body of the post. By 'burning cd' it is currently unknown if your model Mac has a CD or CD / DVD burner inside. If such a device is not inside your model Mac, what type (manufacturer and model number, and type of connection [USB, USB 2.0, Firewire]) external CD or CD / DVD burner do you have?
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'I have purchase a used 10.0 updated to 10.4 Tiger', from where?; for how much (optional)?; and, how do you specifically know that this disc (these discs) will update your current version of MacOS X to 10.4.0 ('Tiger')?
