By default the current day is highlighted. To highlight (an)other day(s) use cw and cdow. cw gives the week and cdow the day of the week to be highlighted.
Together they determine a specific day to be highlighted.
cw alone will highlight the whole week.
cdow alone will highlight the given week day for the whole month.
A given month of this year can be specified with 1. Alternatively, m can be used. Perhaps you want a different title e.g. {{ISOCALENDAR|This November|m=11|y=2006}}.
You can highlight "Saturday of week 3 in January 2021", "all of week 6 in February 2021", or "all Thursdays of March 2021" like this:
{{ISOCALENDAR|January 2021|cw=3|cdow=Sat}}
{{ISOCALENDAR|February 2021|cw=23}}
{{ISOCALENDAR|March 2021|cdow=4|hideweek=yes}}
January 2021
Week
Mon
Tue
Wed
Thu
Fri
Sat
Sun
W53
28
29
30
31
01
02
03
W01
04
05
06
07
08
09
10
W02
11
12
13
14
15
16
17
W03
18
19
20
21
22
23
24
W04
25
26
27
28
29
30
31
February 2021
Week
Mon
Tue
Wed
Thu
Fri
Sat
Sun
W05
01
02
03
04
05
06
07
W06
08
09
10
11
12
13
14
W07
15
16
17
18
19
20
21
W08
22
23
24
25
26
27
28
March 2021
Mon
Tue
Wed
Thu
Fri
Sat
Sun
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
01
02
03
04
Highlighting a specific date based on a timestamp is somewhat more difficult, because you can't just pass the date into this template, you have to calculate the week number and day of week. Luckily, we have ParserFunctions that can parse all sorts of time data (in which there are even ready-made functions to get zero-padded ISO 8601 numbers: W for week and N for day-of-week). This can be done like so:
